June 3rd, 1940.
Ship's captain William Tennant sends a coded message.
"Operation completed. Returning to Dover."
The so-called small ships flotilla of over a thousand vessels
has rescued more than 300,000 soldiers of the British
Expeditionary Force from the French port of Dunkirk.
A 3:40pm the next day, as the last of the French rearguard clamber
aboard British rescue ships,
Prime Minister Winston Churchill stands before Parliament.
At this point, that German Army
and Air Force was looking across the Channel
so Churchill actually has to rouse the British people and warn them
that the Germans are on their way.
To do this, he makes one of the most memorable speeches in history.
We shall fight on beaches,
landing grounds,
in fields, in streets,
and on the hills; we shall never surrender.
This will become one of the most quoted speeches of all time,
but behind its defiant bravado hides an unspoken truth.
Churchill sat down. He's supposed to have said to a colleague next
to him, "We'll fight them with the shattered ends
"of beer bottles because that's all we've damn well got."
About three in five of the British
army's tanks and artillery are left
behind in the chaotic retreat from Belgium.
If Hitler had chosen to invade at that point, it is difficult to see
how the country could have defended itself
because they didn't have weapons.
Hitler intends to knock Britain out of the war and quickly
turn his attention to his real target - Russia.
But he has reckoned without the Royal Air Force.
The scene is set for an epic confrontation.
But what will become known as the Battle of Britain
will not only come down to numbers.
It will also come down to time.
Between June and October, 1940,
the nature of warfare changes forever. The Second World War
really marks a step change in the way that wars are fought.
Because, before the war, you had to control the land
and sometimes the sea.
Now, you also have to control the air.
The essential prerequisite for any successful invasion
had to be German command of the skies over the Channel, and,
for that, the Royal Air Force had to be defeated.
There was no doubt that you had to achieve air supremacy.
Reich's Fuhrer, Adolf Hitler, is well aware of this.
Operation Sea Lion, the codename for the German invasion of Britain,
requires 13 divisions to be transported across the Channel
to a series of landing points along a 190-mile front
stretching from Ramsgate to Lyme Regis.
For that to work, three things had to happen.
First, the Royal Navy had to be defeated for the Channel.
Secondly, the defences at the beachheads
had to be pounded into submission.
Third, in the event of a successful invasion, the supply lines
had to be protected so the British couldn't cut them off.
Now, to do all that, you need the Luftwaffe.
Nazi Air Marshal Hermann Goring is confident that his Luftwaffe
can swat the British out of the sky with ease.
"I'll do it in four days," Goring said.
He was a boastful man, but he did have genuine reasons for believing
that the Luftwaffe could gain the upper hand over the Royal Air Force.
The fact was that the Luftwaffe pilots were more experienced
than Royal Air Force pilots.
They'd already learned their craft in Spain before the war,
then in Poland.
In June 1940, Goring also has more aircraft at his disposal.
To spearhead what will become known as the Battle of Britain,
the Luftwaffe has over 900 fighter aircraft.
British Air Chief Marshal Sir Hugh Dowding can muster 768 fighter
planes, of which only 520 are serviceable.
There's no doubt about it.
Fighter Command of the Royal Air Force had been badly hit
by the Battle of France and Dunkirk.
Something like a third of British planes had been put out of action.
Worse still, at the start of the war, German factories are producing
almost 550 planes a month.
By contrast, British production of aircraft was comparatively pitiful.
Confident he can replace all the combat losses he might incur,
Goring believes he has the numbers and that the Luftwaffe outclasses
the RAF in virtually every important respect.
He's particularly bullish about his fighter pilots and their aircraft.
This is the Messerschmitt Bf 109,
the principal Luftwaffe fighter aircraft of the Battle of Britain.
In fact, this one actually served in that combat in 1940.
This aircraft is a remarkable machine in many ways.
Got a maximum speed of 350mph.
It can fly up to 35,000 feet.
Got cockpit armour, which is very, very good for the pilot,
and very, very well armed - up to three cannon and two machine guns.
Crucially, these pilots, some of them had served in the
Condor Legion in Spain, where they'd escorted bombing missions.
They knew what they were doing.
Ranged against the Messerschmitt is this aircraft.
This is the Hurricane.
Not nearly so well known as the flashy and iconic Spitfire
over there, but this is the real workhorse of the RAF.
It's an aircraft which is robust, easy to repair,
but it has some problems.
It's only got a maximum ceiling of 16,200 feet
and can only fly at 324mph.
Very importantly, it lacks cannon.
This aircraft does not have the firepower of the Messerschmitt.
With only eight machineguns, it does not have the punch of its opponents.
Other problem is this...
it's got three fuel tanks - one each wing,
one directly in front of the pilot.
If that fuel tank is pierced,
then fuel will flood back over the pilots
and the problem is that the canopy is difficult to open.
Some pilots find it difficult to bail out;
others, I'm afraid, never make it.
However, the great advantage of this aircraft
is the turning circle.
The result is that you turn inside your opponent in a dogfight
and that's the difference between life and death.
The decisive battle for supremacy of Britain's skies
does not happen for several weeks.
When it does, the numbers will surprise both sides.
As well as winning air supremacy,
victory in the Battle of Britain requires the Luftwaffe to clear
the British Navy from the English Channel.
Air Marshal Dowding identified July 10th as the first major day
in which the Luftwaffe were bombing, but actually the Luftwaffe
had mounted plenty of sporadic attacks before then.
Despite this, the Royal Navy are still sending convoys
through the Channel until, one day, a convoy of 20 ships
loses all but four of its number.
The battle for the skies does not truly take off
for several more weeks, and the reason for that is Hitler.
What Hitler wants Britain to do is to come to terms.
He wants to make peace with them
because he can't understand why Britain won't make peace.
Britain is a busted flush, as far as he's concerned.
Convinced that Churchill will surrender, Hitler waits until
August before ordering an all-out assault on Britain's airbases.
It's just the kind of breathing space that Air Marshal Dowding
is praying for.
Dowding did need time to bring more planes into action, to fix,
to repair some of the planes that he already had, to train up pilots.
August 13th, 1940.
The Germans unleash a massive air raid.
On Adlertag or Eagle Day, 1,485
German aircraft bomb Britain's airfields and plane factories.
But Eagle Day is only the beginning.
The merciless bombing raids continue for the rest of a month
in which Britain's skies swarm with German aircraft.
At the height of the Eagle campaign, more than 1,700 bombers
are accompanied by fighter escorts.
BELL RINGS
But Dowding's RAF is ready for the Luftwaffe.
By the time of Eagle Day, Fighter Command has over a thousand
fighter aircraft and they are eager to have a scrap.
British Fighter Command also has a technological advantage.
They're backed up by an early warning system of 21 radar stations
and 30,000 spotters that can detect enemy aircraft
from up to 80 miles away.
One aspect of war for which Britain was brilliantly prepared in 1940
was home defence against air attack.
And this marriage, not only of the radar system, not only
of the Spitfires and the Hurricanes,
but also of the rhetoric of Winston Churchill,
these things came together to create something absolutely astounding
in the eyes of the world.
The Luftwaffe is astonished.
At least three quarters of its raids are being intercepted.
On Eagle Day itself, the RAF shoots down 46 German planes
for just 13 of their own.
On August 18th, the so-called Hardest Day, 69 German aircraft
are shot out of the sky for only 31 British.
Right from the start, the RAF are winning the Battle of Britain.
But it doesn't feel like it.
At the height of the Eagle campaign,
four airfields are temporarily put out of action.
And the number of air crew getting killed is phenomenal,
which means you've got these young pilots with just ten hours' training
coming into full combat service.
But numbers can be deceptive...
especially when you're getting them wrong.
For most of the Battle of Britain,
the intelligence on both sides was actually faulty.
The popular image of the Battle of Britain, of course,
is David and Goliath. British Fighter Command is David
and there's this huge German Goliath, you know,
who's got absolutely masses of aircraft.
Well, it's an attractive story but there were more fighters
available to the British than were available to the Germans.
At the height of the Eagle campaign, the Germans are convinced
that the RAF has lost 770 planes
out of an available force of 1,200.
In fact, they've only lost 318
and still have 1,400 available.
And new plane production is now so fast that there are over three
times more in service than the Luftwaffe estimates.
Since June, British aircraft factory output has soared to 1,900
new fighters in just three months.
Germany doesn't know it, but in British factories an ambitious
programme of aircraft production named Harrogate
has been operational for months.
They plan to produce round about 3,000 aircraft.
In the end, they end up producing more than 4,000.
There's a general sense of urgency.
Workers are willing to turn up and work all night.
If we can't get the aircraft out fast enough,
then the worst is going to happen.
Even so, the combined toll of more than 1,300 German aircraft
pounding British airfields every clear day
is pushing the RAF to breaking point.
The leaders of Fighter Command started worrying
that they couldn't actually maintain the fight;
they were going to have to move the airfields back.
The RAF feels like it's on the verge of collapse
when, on September 7th, the Germans launched the heaviest single raid
of the campaign.
Goring thinks that the RAF is finished
so they go onto the next stage of supreme invasion plan.
348 bombers accompanied by 617 fighters
start flying across the Channel.
But today their targets are not airfields.
They have one target and that's London.
At 5pm, German bomb doors opened above London's docks.
They dropped more than 350 tonnes of high explosive
and over 400 incendiary bombs.
The inferno was so big,
it caused more damage than the Great Fire of London.
Ten days earlier, 95 British aircraft had bombed Berlin.
The bombing of London's dockyards
marks a decisive change in Nazi strategy.
The bombing of London is often
seen simply as a reaction by Hitler to the bombing of Berlin.
Let's teach the British a lesson.
In fact, the bombing of London had long been part of the plan. The idea
was that there would be serious and heavy attacks on London
to disrupt the capital, just a week before German troops began to land
on the Sussex and Kent coast.
But in fact, the Blitz of Britain lasts eight months.
More than 30,000 tonnes of bombs are dropped on London and other cities;
over 40,000 perish.
250,000 people are rendered homeless within the first month
and over two million homes are all destroyed.
But British morale remains unbowed.
It's often said the Blitz spirit was a myth.
It's not true.
Blitz spirit was not a myth.
Blitz spirit was real.
The Blitz never really came close
to shattering the morale of the British people.
The Luftwaffe suddenly threw sufficient numbers
at breaking Britain's spirit.
Just after midnight on September 15th, 1940, Goring sends in wave
after wave of bombers, forcing the RAF to face his fighter escorts
in dogfights over London.
September 15th is still commemorated as Battle of Britain day.
The raid lasts 19 hours.
Our best guess is that something like 1,500 aircraft took part.
And the British estimated that they shot down 185 German
aircraft for the loss of 29 aircraft of their own.
In fact, only 74 German aircraft are destroyed.
But it's enough to convince Goring that daylight bombing
raids are too costly to continue.
From that day, the German blitz is only conducted at night.
The Battle of Britain is effectively over.
In the end, for the Germans the Battle of Britain
was an unwinnable battle.
The level of attrition that the German air force had to take
during this period was enormous.
The loss rates were catastrophic loss rates.
It's the day when Hitler effectively threw in the towel,
gave up on the invasion of Britain, and turned his attention elsewhere.
Hitler has other things to focus on rather than some tinpot island
on the edge of the Atlantic.
No, he's planning something else.
He's planning to conquer Russia.
The conquest of Russia has always
lurked at the centre of Adolf Hitler's plans.
As early as 1923,
he identifies Russia and the Ukraine
as places which are ideal for the Lebensraum,
the living space that he needs for the German people.
The idea was to create colonies that could be sort of farms
for Germany but also give them lots of mineral resources -
coal, oil and so forth.
The plan, basically, was for the native population,
who were considered Untermensch - "under beings" -
to be cleared out of these areas.
This was a murderous plan in its basic inception.
A certain portion of them were going to be starved.
A certain number of them were going to be killed, worked to death.
Even though Britain is inconveniently holding out
on the Western Front, Hitler decides it no longer matters.
When Hitler is controlling that vast swathe of European Russia,
Britain will no longer have any allies left in Europe, and so
she'll just have to sue for peace.
By June 1941, Hitler and his yes men in the German High Command
convinced themselves that a blitzkrieg through Russia
can take Moscow in three months.
If the French army could be defeated in six weeks,
the premiere army in Europe as far as they were concerned,
then the Red Army is no... it's a paper tiger.
To use the word "hubris" to describe the German mood
after their huge successes in France in 1940 isn't enough.
Hitler's faith in the German army was overwhelming.
The Reich's Fuhrer also takes encouragement from the Red Army's
wretched performance in its November 1939 invasion of Finland.
The so-called Winter War sees over a million Soviet soldiers fought
to a standstill by a mere 300,000 Finns.
Russia's casualty rate is also seven times that of Finland's.
The idea that the Red Army were going to be able to
resist the Germans seemed absolutely incredible.
But Hitler failed to notice two things.
The first was that the Russian army was very good at adapting.
They learned from their mistakes. And the second thing that Hitler
failed to appreciate was that Red Army tactics simply rely on wave
after wave of humanity overwhelming enemy positions.
This was the preferred tactic of General Georgy Zhukov,
whose recent success against the Japanese in Manchuria
has promoted him to the top of Stalin's purged officer corps.
Just in time to come face-to-face with blitzkrieg.
Stalin has huge numbers of intelligence warnings -
84 in number - saying the Germans are going to attack us,
there's no doubt the Germans are going to attack -
and Stalin disregards them all.
Under the Soviets' non-aggression pact with the Nazis,
in the first year of the war the Russians are giving the Germans
900,000 tonnes of oil,
one million tonnes of cereals
and half a million tonnes of weapons grade phosphates.
Stalin is convinced such essential commodity trade
will keep his borders intact.
But the evidence suggests otherwise.
Three spies even gave him the exact date on which Hitler
was going to invade, but again Stalin ignored it.
On June the 22nd, 1941,
Hitler sends the largest invasion force ever assembled into Russia.
More than 3.6 million men,
7,000 artillery pieces,
3,500 tanks and 2,500 aircraft
supported by over 600,000 horses
are heading Stalin's way.
Despite repeated warnings, the Soviets are totally unprepared
for Germany's Operation Barbarossa.
Barbarossa was the single most important act of the Second World
War, which completely transformed its character
and it represented the fulfilment of Hitler's foremost dream
of Lebensraum, of a triumph
over the Jews and the Bolsheviks.
And also providing the German people with this empire in the east
with a vital source of food and oil.
Southern Russia, Ukraine and Caucasus
in particular are incredibly rich in mineral resources.
We're talking about oil.
We're talking about coal - enormous coal reserves there, too.
There's food and there's enormous amounts
of wheat fields in southern Russia and in Ukraine.
On paper, the Red Army has formidable forces at its disposal.
At least five million men,
10,000 tanks and more than 6,000 planes available.
But 70% of its force is spread out, occupying Poland the country
that Stalin and Hitler partitioned as allies, just a few months ago.
Despite all 84 intelligence-led warnings of an invasion, Stalin
finds the German assault so shocking that he has a minor breakdown.
This is a man who still can't believe this is happening.
He goes to his dacha, his country house, and he spends three days
there in isolation, refusing to see anybody.
By the time Stalin takes control,
the Germans are 400 miles into Russian territory.
And the Red Army has lost almost 5,000 tanks
and close to 2,000 planes.
The initial blitzkrieg into the Soviet Union
actually went very well indeed.
The Russian Air Force, for example, lost more planes than the British
lost during the entirety of the Battle of Britain.
Goring is ecstatic.
Blitzkrieg is proving so effective that entire Russian armies
are cut off and forced to surrender.
By the middle of July, less than a month after the start
of the campaign, 300,000 Russians had been taken prisoner.
And, in fact, Franz Halder, the Army chief of staff,
declared that the whole war had been won in just 14 days.
But there is a lot of fighting yet to come.
The German invasion plan involves a three-pronged attack.
Army Group South will strike the rich Russian heartlands
of the Ukraine and Crimea.
Meanwhile, Army Group North and Army Group Centre will push north
of the impassable Pripet Marshes,
then divide at Smolensk.
Army Group North will swing up to Leningrad,
while Army Group Centre will smash through to Moscow.
For Hitler's generals, Moscow is the absolute key.
If Moscow falls, they say, then Russia will fall with it.
The Nazis wanted to take Moscow for good military strategic reasons,
in part. If you visit Russia, you'll see that
all the train lines converge in Moscow.
All the transport networks, the canals, the road network,
they all go through Moscow
so capturing Moscow would have been an important blow
against the Soviet Union.
But Hitler disagrees with his generals.
For him, taking the resource-rich bread basket of the Ukraine
and the oil fields of the Caucasus is just as important
as the symbolism of taking Moscow.
Russian oil and Russian corn was absolutely vital to Germany
to continue with the war.
Once Barbarossa had been launched, there are train loads of corn, oil,
every sort of commodity flowing from Stalin's Russia
to Hitler's Germany.
So much Soviet food in the bellies of German troops
inevitably leads to famine.
The German Army are being fed by those fields -
that raises the obvious point...
What's going to happen to the 30 million Russians
who are normally fed by those fields?
Well, the solution is very simple.
They all have to starve to death.
Genocide is at the heart of Lebensraum.
But, in Russia, the Nazis miss a trick.
The population they are starving might even have supported them.
The Soviet Union was a very brutal place and it had alienated
large parts of its own population.
Collectivization was not popular with peasants,
to say the very least, so the rural peasantry are an obvious
constituency the Nazis could have courted.
But the Nazis' own brutality towards these people, whereby
they treated them as inferior human beings, meant that whatever
tentative practical steps they might have to reach out to that population
were undermined by their own brutality, their own racism, their
own violent, thuggish, colonial attitude to these people.
And for Russian soldiers, the destructive logic of Lebensraum
makes even surrender fatal.
By the end of September,
2 million Soviet troops have been captured
and, by the end of the war, that's risen to 5.7 million.
And the Germans only had space to hold 790,000 prisoners of war.
So the obvious question is, what happens to them?
And at least 3.3 million Russian POWs are either shot or starved
to death in German captivity.
That's murder.
The civilian population fares no better.
Hard on the heels of Panzer divisions
come German Einsatzgruppen. Death squads.
We tend to think of the Holocaust happening just in places
like Auschwitz and in gas chambers, but actually millions of people
were simply shot to death by these SS units
called the Einsatzgruppen.
This didn't just include political figures like Soviet commissars,
but Jewish, men, women and children too.
The most infamous mass shooting of Jews by the Einsatzgruppen
in the former Soviet Union occurred
at Babi Yar, a ravine outside of Kiev, in September 1941.
The local Jews were taken out to this big ravine near Kiev
and they were forced to undress,
stand at the edge, and be shot into it.
And something in the region of 33,000 Jews were shot.
It was one of the largest massacres of that sort during the war.
There are hundreds of such places throughout the former Soviet Union.
Ultimately, we think that something like 1.5 million
Soviet Jews were murdered by the Nazis.
Jews, gypsies, homosexuals, the mentally ill - anyone deemed
a threat to Aryan superiority becomes a target.
They were people like the famous Dynamo Kiev football team
that defeated a Nazi team in an infamous football match.
They were anybody of that kind.
Those they don't kill, they enslave.
Some seven million Eastern Europeans
are sent into labour battalions, and they're brutal places.
On the battlefield, the number of Russian casualties
is equally unimaginable.
44,000 soldiers fall every single day.
The Nazis are pouring hellfire down upon the Great Bear,
but Hitler has not won yet.
There are two military aphorisms that every soldier knows
and that Hitler ignored at his peril.
The first is that no plan survives contact with the enemy.
The second, never fight a land war in Asia unless you're heading west.
Hitler ignores both of them, and that will prove to be a big mistake.
The Barbarossa invasion plan assumes the Red Army is so weak
that a German blitzkrieg will take Moscow in three months.
But the plan seriously underestimates both its opponent
and the Soviet Union's sheer size.
He can't even conceive of the challenges of space,
the challenges of scale that he's confronting
in the former Soviet Union.
It is the biggest country in the world and that's really key here.
The Soviet Union is not only land-rich; its 170-million-strong
population provides Stalin and his chief of staff Marshal Zhukov
an almost limitless resource of fighting men
and almost a million women conscripts.
The Soviet Union put women into arms
like no other belligerent state in World War II.
They were often in highly technical roles - snipers,
they were in tanks, they were radio operators.
The bravery and valour of Stalin's female fighters
soon provide him propaganda gold.
A whole number of women became heroes of the Soviet Union.
People like Zoya Kosmodemyanskaya,
the famous partisan tortured and hanged by the Nazis,
and they took photographs of this whole process
that were published then in the Soviet press.
They sort of mobilised their own population
to avenge this awful and heinous crime.
But when the crunch comes, what will define the battle
between the world's two most hated dictators
will not be Russia's thirst for vengeance.
It will be the weather and, most crucially, the numbers.
By December 1941, Soviet commander Marshal Zhukov has 200
new divisions ready to throw into the fight
against the German invaders.
Russia possesses the numbers to repel the Nazis,
but her troops lack equipment.
The Soviet Union was really good at churning out stuff
that those in power thought that people needed, and it actually
was really poor at producing the stuff that they actually needed.
One glaring example of this is this one Garrison division in Leningrad
that's got just 21 machine guns, about 100 pistols and 300 rifles,
all to share between 7,000 men.
Armed or not, the ruthless Zhukov sends his troops into battle,
often with just Dutch courage to protect them.
Russian soldiers are equipped with 100g of vodka a day
to get them drunk enough to give them the courage to charge
across no-man's-land.
The communist disregard for human life is shocking.
For every one soldier killed or wounded on the German side,
on the Russian there are no fewer than 20.
Zhukov simply doesn't care how many he must sacrifice.
In essence, Zhukov's principal strategy is very simple.
It involves sending more human beings at the enemy
than the enemy has bullets to fire at them.
And around 300,000 who refused to fight
are simply executed by the NKVD.
German manpower resources are stretched to their limit.
It starts to dawn on some German minds that maybe, just maybe,
Hitler has bitten off more than he can chew.
By the end of July, Barbarossa's three army groups sustain
a combined total of 213,301 losses.
But German High Command can only supply 47,000 replacements.
Franz Halder - now, this is the man who would prematurely declare
victory within 14 days - was now writing in his diary,
"We reckoned on about 200 divisions but we've already counted 360,
"so, if we smash a dozen, they'll simply put up another dozen."
If the numbers aren't bad enough, the sheer logistics of getting men
and materiel to the front line is also proving a challenge.
Simply supplying Army Group Centre requires running some
25 goods trains every single day,
and the problems with the Russian network means that, at most,
the Germans are getting eight through, because around 350,000
partisans are operating behind German lines.
In the eyes of Hitler's generals, though, the gravest error of all
comes in August when the Fuhrer orders Guderian 2nd Panzer Group
away from Army Group Centre's advance on Moscow
and sends them south instead.
Guderian was absolutely incensed with this, but actually Hitler
did it for a pretty good reason,
because Army Group South was getting bogged down around Kiev
and desperately needed to be helped.
Not only did the Germans take Kiev,
the Russians lose a massive 616,000 troops in the process.
But just as his generals predict, Hitler's victory at Kiev
takes its toll on German efforts to seize Moscow.
Without Guderian Panzers, Army Group Centre can't push
on towards Moscow and its advance just turns into a crawl really.
The advance on Moscow does not regain momentum until early October.
By then, it is too late.
Russians have a name for their autumn rains.
Rasputitsa.
The dissolving of the roads.
Most roads in Russia, particularly at this time, were mud roads,
meaning that when it starts to rain
torrentially, for days on end,
they will turn to mud and be almost impassable.
So launching their assaulting against Moscow in October 1941,
this was a problematic time because the mud meant they couldn't move
at the lightning pace that they'd previously been able to
when defeating France, Holland, and so forth.
Guderian returns to Moscow from Kiev,
but his tanks grind to a muddy halt.
They're just nine miles from the capital.
One has to remember how narrowly the Russians held on in October.
If those forces which had gone south had been up there in the north,
it's very doubtful that Moscow could have held.
Whether Stalin could have survived, whether the Soviet Union
could have carried on with the war.
Hitler, who does not trust his own army's high command,
takes control of German forces.
His tactic is simply stand and fight.
Much to his generals' chagrin.
And as a result millions of Germans will die.
By December, the Germans lose more than 800,000 men
and haemorrhage 2,000 casualties every day.
And that's before winter sets in.
Winter is the Russians' secret weapon.
It gets so cold.
The temperatures in that winter fell at times
to minus 40 degrees Celsius.
The Germans had no clue how to conduct a war
in those circumstances, and they were very bad at it.
Even their weapons cannot cope with the extreme cold.
This is a German Mauser Carbine.
Typical weapon of any soldier.
To make it work what you have to do is bring back the working parts,
put in five bullets.
Push it forward and then pull the trigger, eject, and so on.
All of that requires lubrication.
If this thing isn't lubricated it will not function.
And that's fine in normal temperatures.
The problem is, that in the Russian winter,
the gun oil actually freezes solid.
It stops being a liquid and becomes like this.
Under those circumstances it stops being a rifle, it becomes a club.
And the fact is the Russians have lubricants that work
at low temperatures. The Nazis don't.
Many German troops don't even have overcoats to protect them
from the cold.
This great mighty German army,
their soldiers are reduced to putting layers of newspaper
under their tunics to keep out the icy cold.
Things get so bad, Propaganda Minister Joseph Goebbels
launches an appeal.
The German public sends 67 million items of winter clothing.
But charity woollens can't prevent vast numbers of soldiers
from freezing to death.
In January 1941, a fierce counterattack is launched
and starts to push the enemy back.
The German blitzkrieg is over.
Operation Barbarossa is staggeringly costly to the German war effort.
Germany begins the invasion with around 163 operational divisions,
and just a year later, they're down to 58.
But this was absolutely catastrophic.
And ultimately the defeat that Moscow was the beginning
of the end. That really was a turning point in the war.
Barbarossa failed to achieve any of its objectives.
Blitzkrieg fails for the first time.
And Hitler has only himself to blame.
In classic dictatorial fashion, when faced with impossible odds,
Hitler doubles down.
On December 7th, 1941,
Japan bombs the Americans at Pearl Harbor.
And within a few days Hitler has declared war
on the United States.
This is absolutely insane.
He's not just now waging a war with the biggest nation on Earth,
he's now waging a war with the richest nation on Earth.
But Hitler is operating on a different plane
to the rest of the world.
One of the factors that clearly plays a part in Hitler's decision
to declare war on the United States is his warped view
of the Jewish conspiracy.
There were Jews all around Roosevelt, so he says.
And therefore, the declaration of war
on the United States is a declaration against world Jewry
as well as against the United States.
The Japanese have handed Hitler the perfect excuse
to turn this into a worldwide war against the Jews.
Why the Japanese would risk the wrath of the greatest nation
on Earth is another story altogether.
One rooted in numbers.
October 1940.
In a tight presidential election Franklin D Roosevelt is running
for an unprecedented third term.
As war rages across Europe he sends a message to the American public.
I have said this before.
But I shall say it again and again.
Your boys are not going to be sent into any foreign war.
CROWD CHEERS
The American public are almost universally opposed
to the idea of going into war.
So if Roosevelt gets branded as a warmonger he's going
to lose that election.
Even after the fall of France in 1940,
over 85% of Americans oppose sending US troops into an overseas conflict.
Less than 16% of the American public support even sending aid
to the beleaguered allies in Europe.
He could see the signs and he knew the United States would eventually
have to enter this war on some level.
But he has a voting base that he has to answer to.
FDR wins the election, but he cannot keep his promise.
BY the end of Roosevelt's time in office,
nearly 15 million Americans will have fought in this world war.
Summer 1940.
Even as President Roosevelt's promises to keep America
out of the war, on the other side of the Atlantic a beleaguered
Winston Churchill is looking for a fight.
Britain is in pretty dire straits.
The Battle of Britain is being waged overhead.
The British Expeditionary Force has been thrown out of Europe.
So what is needed is some kind of arena,
some kind of theatre of war where Britain can fight
and where Britain can succeed.
Churchill finds it in the Mediterranean.
The Mediterranean theatre wasn't just important
as a means of allowing the British to fight.
It was actually strategically very, very important.
We actually got our oil from the Persian Gulf
That had to come through the Suez Canal through the Mediterranean.
If Britain was to be thrown out of Egypt it would lose
that access to its oil.
The Middle East can provide Britain with over 126 million barrels
of oil a year.
It's a vital resource transported from the Persian Gulf
through the Suez Canal.
In June 1940, Italian dictator Benito Mussolini,
who already controls neighbouring Libya, decides to take Egypt
and its precious waterway.
Mussolini had real delusions of grandeur,
a sense of his own importance.
He sees Adolf Hitler in Germany grabbing for territory to create
a new German empire.
And what Mussolini wants to create is a new Roman Empire
in the Mediterranean basin.
The plan basically was to seize control of the entire North African
coast, to take it away from Britain.
It's the fight that Churchill is looking for,
but the numbers weigh heavily against him.
250,000 Italian troops land in Libya and march on Egypt
against a mere 36,000 Brits.
On paper it looks like it's going to be an easy campaign.
But the battle wasn't carried out on paper.
A sudden attack by the British forced the Italians back.
By February 1941, the British have advanced 500 miles.
Captured 130,000 Italians,
380 tanks and 1,290 artillery guns.
Britain loses less than 2,000 killed and wounded.
A furious Hitler diverts to the desert two divisions earmarked
for the invasion of Russia.
Named the Africa Corps, the new force is commanded by General Erwin Rommel.
Rommel's leadership was what turned the Africa Corps into one
of the most iconic units of the entire war.
Because British tanks outnumber Germany's by more than three to one,
Rommel is advised not to attack.
But Rommel simply ignored what he was told.
He saw his opportunity and he launched a sudden attack.
It might seem suicidal, but Rommel has an ace up his sleeve.
The 88 millimetre flak cannon.
Designed as an anti-aircraft gun,
Rommel knows that it's also an effective tank killer.
Just like he did in France,
Rommel drew out the British forces
into an area, ambushed them then with the 88 millimetre guns.
It took the British completely by surprise.
What the British had just done to the Italians,
Rommel did to the British.
By April 1941,
Churchill's initial desert victory is in tatters.
Rommel has the British under siege at Tobruk and they have more
to worry about than just North Africa.
Because Mussolini has taken the fight to the Mediterranean.
After a botched invasion of Egypt,
the Italians preside over a botched invasion of Greece.
In response Churchill diverts 62,000 troops from the desert
to defend Greece.
Churchill sees this as a great opportunity to score yet another
quick victory over the Italians.
But the problem is, Hitler then looks at what happens
and decides he has to clear up the mess,
just as he did in North Africa. What does that mean?
The British are now fighting a far more capable German force.
In less than three weeks Hitler's Panzers overrun both
Greece and Yugoslavia,
forcing the British to evacuate 43,000 troops
to the island of Crete.
Hitler responds by launching an airborne invasion of Crete
with up to 30,000 paratroopers backed by 480 bombers.
British forces are effectively trapped.
Winston Churchill orders General Wavell to stay there and fight to the last man.
Wavell realises that it's not a good idea and defies the order
and evacuates 16,500 men.
Wavell is dismissed for disobedience.
But his decision saves British lives.
16,500 men live to fight another day.
If that had been Hitler those 16,500 men
would have been needlessly squandered.
These events profoundly affect the war, even
outside the Mediterranean, because the time it takes Hitler
to chase the British out of Crete
has a domino effect on Germany's invasion of Russia.
By delaying Operation Barbarossa even by one month, that pushes
the Germans one month closer to the onset of Russian winter,
and Russian winter will grind them to a halt.
The situation in the Mediterranean is absolutely crucial
for the outcome of the war.
The British troops evacuated from Crete are sent back
into the desert against Rommel.
But the conflict will soon find itself mired in the vast expanses
of the desert itself.
First, the British had the upper hand...
..then the Germans took the upper hand,
then the British took it back,
and the reason for that was because of supply lines.
Germany's supply line starts in Tripoli,
Britain's in Alexandria -
a distance of almost 1,200 miles of desert that makes sustained
advance by either side too difficult to refuel and rearm.
The result is inevitable -
deadlock.
There was no obvious end to this.
What was actually going to change, make a sudden difference
and end this conflict?
The surprising answer will take place on a tiny island
on the other side of the world.
June 1941.
Over four million soldiers are locked in a devastating campaign
across a 2,000 mile-long front.
In what is already one of the bloodiest conflicts in human
history, the invading army grinds forward
into a seemingly endless country...
..China.
The campaign in China is a major all-out continental conflict
for the Japanese
that is costly.
Japan has already lost over 1.8 million soldiers...
..and committed more than 70% of its economy to war.
The Japanese had got themselves into a situation where they felt
that expanding the war was the only way that they could bring
about a conclusion.
A Japanese occupation of key airfields in Indochina greatly
worries the American president.
Roosevelt is in a really tricky position.
He really wants to stop this Japanese expansion throughout
Asia, but he can't do anything about it militarily,
so what does he do?
He's got to use America's economic muscle.
Roosevelt takes the decisive move of freezing Japanese assets
in the United States, which freezes millions and millions of yen.
That then turns into this outright all-encompassing oil embargo.
Japan imports 90% of its oil from the US.
And for the Japanese, that feels like castration.
To further demonstrate America's resolve,
USA to China is doubled.
The powerful Pacific Fleet sails out of California
to Pearl Harbor in Hawaii.
35 B-17 bombers are based in the Philippines, within striking
range of Japan.
Roosevelt's hoping that if he flexes his military muscle then Japan
will back down.
But he's reckoned without Japan's desperate need for oil.
The Japanese were backed into a corner, and they basically
had two options.
Option A was that they could discontinue the war in China,
which was certainly the American objective, or option B
was that they could double down and expand war in Asia,
and the Japanese chose Option B.
The Japanese army is under the control
of General Hideki Tojo, aka the Razor.
In October 1941, Tojo becomes Prime Minister, and draws up plans
to create a new Japanese Southern Resources Area.
The Japanese military began to think,
"Well, where can we get additional resources?" and the obvious place
is South East Asia.
Resources from the British were there, from Burma,
from Dutch East Indies and so on.
It's a plan to take over all of Southeast Asia.
Its codename is Operation Z.
Operation Z allows 50 days for the conquest of the Philippines,
100 days for Malaya and 150 days for the Dutch East Indies
before pushing on into Burma and even India.
Tojo's plan amounts to conquering roughly a sixth of the world's
surface in just six months.
Doing so will make armed confrontation with the industrial
might of America unavoidable.
At first glance, this seems insane.
This is crazy.
Japan has got to land a knockout blow in the very first round
if she wants any chance of succeeding.
The USA is the largest economy in the world, producing more steel,
aluminium and oil than every other major state combined.
It produces goods worth over $1 trillion a year.
Japan's economy produces only $196 billion - more than five times
less than the USA.
But these numbers count for nothing to Tojo, because Japan has one thing
the Americans can never match...
..warrior spirit.
If you join the Japanese army at that point, the training
was very focused, inspired by tradition of what was known
as Bushido - The Way Of The Warrior.
There was a strong psychological
element that enabled the Japanese to feel that there was something
superior and resilient about the Japanese military training.
By contrast, they think that the Americans are kind of soft,
and a bit lily-livered - just a nation fit for making movies
and motor cars with no stomach for war.
Many of the Japanese leaders thought that if they could hit the Americans
hard enough they would make terms immediately.
They certainly didn't think of them as real warriors,
people who could resist Japanese soldiers for five minutes.
Tojo has also run the numbers, and he believes the Americans aren't
ready to fight.
You might expect that the world's most powerful economy
is going to have a military to match it,
but, in 1941, the American economy is not geared for war.
It's geared for commerce.
In 1941,
American military spending accounts for just 2% of its national output,
compared to Japan's 70%.
The United States actually had a relatively small army.
It was the 18th largest army in the world.
The United States of America was unprepared for war,
but the United States had an excellent navy,
and the United States - in the interwar period - had developed
naval aviation to a level that it was among the leaders of the world.
All of America's strength lies in its navy.
In almost every class of ship, its power in the Pacific is almost
equal to Japan's.
But without its warships,
America cannot hope to repel a Japanese onslaught.
The Japanese thought that once you neutralise
the American Pacific fleet, they would be reasonably secure.
The Americans would huff and puff,
but not actually engage in serious war.
Tojo needs to take out the US Navy,
and his intelligence network provides him with the opportunity.
He finds out this vital piece of intelligence that the entire
US Pacific Fleet is going to be at Pearl Harbor in Hawaii.
Too tempting a target to pass up.
Located 2,500 miles west of Los Angeles,
on the Hawaiian island of Oahu,
the port of Pearl Harbor is the largest
American base in the Pacific,
and on paper it's formidable.
Oahu, by 1941, had been turned into the Death Star.
Oahu had coast artillery positions and batteries,
effectively all approaches were extremely well covered.
They appear strong. In fact, the island's defences are limited.
What Oahu was well prepared for was a direct amphibious
assault that was supported by battleships.
What Oahu was less prepared for was this new thing...
called the air raid.
On 7th December 1941, the first wave of the most powerful naval
air force ever assembled flies low towards Hawaii.
A grand armada of 49 bombers,
40 torpedo bombers,
51 dive-bombers,
and 43 fighters
is heading for Pearl Harbor.
These are very, very experienced aircrew.
They've been fighting in China for four years.
Each man has on average
800 hours of combat experience.
As 183 planes close in,
130 ships of the US Pacific Fleet
sit at anchor in the bay.
And nearly 400 aircraft are parked on the ground.
The position is impossibly vulnerable.
Only a quarter of the machineguns guarding the harbour are actually
manned and the anti-aircraft guns don't even have any ammunition.
And worst still it's the weekend so most of the high command
are taking some time off and leaving just junior cadets in charge.
It's hopeless.
Before a single bomb has been dropped,
commander of the Japanese air fleet Mitsuo Fuchida
gives the victory signal.
Tora. Tora. Tora.
The fighters and the dive-bombers now peel off
and they attack the airbases.
The Japanese were carrying out a well-coordinated attack against
every installation on the island.
The Japanese torpedo bombers, along with five mini submarines,
then go for the battleships.
The Arizona takes a direct hit
and that goes down with its crew of 1,500 men.
Within minutes, Arizona's exploded, Oklahoma is capsizing,
Utah is capsizing.
At 9am, a second wave of 167 aircraft hits the base
to finish off the fleet.
They leave behind a landscape of destruction.
The Japanese destroy 188 aircraft,
damage and sink 21 warships,
and they kill just under 2,500 Americans, both military personnel
and civilians.
But something is missing from the kill list.
Admiral Yamamoto has been told that all US aircraft carriers are absent.
Actually, all the aircraft carriers have been sent to Midway where
they are acting as a kind of forward defence shield,
but Yamamoto suspects they are being held back as a trap.
It's enough to persuade him not to risk one third attack wave
aimed at Pearl Harbor's undamaged refuelling stations.
The third wave could have knocked out Pearl Harbor completely
but Yamamoto simply can't afford to take that risk.
At that point, the fleet had turned and was sailing away.
The day after Pearl Harbor, President Roosevelt makes
a speech to the US Congress, calling for a declaration of war.
December 7th, 1941,
a date which will live in infamy.
United States of America was suddenly and deliberately attacked
by naval and air forces of the Empire of Japan.
But Japanese high command has utterly misjudged the American
response to their attack.
The Japanese attack on Pearl Harbor was extremely effective.
It inspired a hatred of Japan,
a rage and anger
which unified the country as nothing else could have done.
They completely misread that mood.
In Congress, the motion to declare war passes almost unanimously.
Pearl Harbor has united America against the Axis powers...
..and the whole world is now officially at war.
Even as the first bombs drop on Pearl Harbor...
..Japanese forces are already en route to their Southeast Asian
resource zone.
Their biggest target is British Malaya, and its capital Singapore.
It's been said that if India was the jewel in the crown
of the British Empire, then Malaya was the industrial diamond.
In today's prices, Malaya is worth over £10 billion a year,
and 23% of its trade also passes through Malayan ports.
Administering and profiting from this industry are 31,000 Europeans
living a life of Imperial luxury
among five million Malays and Chinese.
Life in the colonies is not really changed since the 19th century.
You've got this endless round of garden parties,
cricket matches, social events.
Physical separation between the white and Asian populations
is enforced in workplaces, restaurants, and neighbourhoods.
The Japanese cite European imperialism in Asia as a key
driver of their expansion into the so-called Southern Resource Zone.
The Japanese used a very strong argument that it was
they who were actually liberating other parts of Asia through
the imposition of their own empire
from the control of the British and the French.
Now, in fact, this was a deeply deceptive idea.
Japanese Empire was often just as brutal or even more so.
When the Japanese invade Malaya,
its defenders are underequipped and undermanned.
There are only ten British battalion stationed in the province,
accompanied by 145 ageing Buffalo fighter
and Blenheim bomber aircraft.
These are not very good planes.
They're slow, they're not very manoeuvrable,
and the Japanese Zero can absolutely outfight them.
On day one, nearly 100 British planes are shot down,
leaving just 50 against nearly 600 Japanese.
But Britain still has its most powerful weapon in hand.
Months before the invasion, Winston Churchill sends to
the Philippines an elite Royal Navy fleet known as Force Z.
Led by the HMS Prince of Wales, Britain's most sophisticated modern
battleship, and the HMS Repulse, it's most decorated cruiser.
Within a day, they are suddenly attacked by the
Japanese Air Force, and the British fleet has got no air cover at all.
Both flagships are sent to the bottom of the ocean,
taking with them the invincibility of the Royal Navy.
These sinkings produce a shock wave that resounds around the world
because these ships have been brought down quickly with
small lightly-armed aircraft.
Having sunk the Royal Navy, Japan sends in 60,000 ground troops.
The ferocity and guile of the Japanese invasion takes
the British by surprise.
Japan's plans depends upon the kind of blitzkrieg tactics that
the Germans used against the French and the Low Countries back in 1940.
But actually Malaya is a very different type of terrain
than Europe.
It's crisscrossed by lots of rivers, it's jungle, and
so motorised transport
doesn't really work as effectively in those sort of conditions.
So, Japan comes up with this ingenious solution -
it's called the bicycle.
This is a 1930s bicycle, not a million miles away from the
bicycle used by the Japanese army in the invasion of Malaya in 1941.
Every Japanese division had 6,000 of these things.
The Japanese soldier could carry himself, his equipment,
and his ammunition, but more importantly you can go
through the jungle with it, you can go virtually anywhere.
Even if a tyre shredded completely, you could run on the rims,
and there are stories about British units panicking, hearing these
metal rims clattering down roads and assuming that they were tanks.
But the key feature of the bicycle is it doesn't require fuel.
The advance can go ahead in almost any conditions without
need for any motor transport.
The British chose to defend the roads
and to position their troops around the roads, and the Japanese
with large forces of bicycles, which they exploited brilliantly,
simply whenever they met them, the British, they went round them.
To reach Singapore, Japan's bicycle army advances on average
12 miles a day for 55 days.
660 miles, 95 fighting engagements,
and 250 bridge repairs later,
they reach their target.
The British simply don't expect any attack to come from the north. Why?
Because it's jungle.
But out of the jungle spring 30,000 Japanese.
The 70,000 defenders are completely unprepared for the Japanese attack.
The numbers favour British colonial forces by more than two to one
but many lack the will to fight.
After years of social exclusion, many of the colonial native
troops are absolutely unwilling to die with their British masters.
Why would they want to?
In fact, some even actually welcome the Japanese troops.
On 15th February 1942, Singapore surrenders.
The British suffer in Malaya, not just a defeat,
but a humiliation, because these despised Orientals,
who were supposed to be near savages,
yes, in the minds of many British people,
they wiped the floor with the British and Australian troops.
The Germans had estimated that it would take 16 divisions and that
it would take months to reduce Singapore and produce its surrender.
And the Japanese did it in a couple of weeks with two divisions.
A bell rings out across Singapore, signalling the surrender.
And there's this classroom of schoolchildren,
they ask their teacher, "What's that bell for?"
And he replies, "The end of the British Empire."
In the Philippines,
and determined to avoid such humiliation, are the Americans.
The Philippines are America's largest foothold in the Pacific
and as a result, Japan desperately needs to conquer them.
The Philippines are commanded by US general Douglas MacArthur.
Within ten hours of the Japanese strike on Pearl Harbor,
he finds himself facing a devastating attack.
The Japanese attack initially comes in the form of air raids...
..followed by Japanese amphibious landings on the island of Luzon,
and General Douglas MacArthur commanding American
and also Philippine forces makes a tactical decision that the way
he will fight will be to back down this peninsular
that's on the western side of Manila Bay, and it's called Bataan.
Besieged by almost 200,000 Japanese troops,
MacArthur is out numbered four to one.
And he has 25,000 civilians under his protection.
Pummelled by relentless Japanese bombardment
and racked with rampant malaria, MacArthur's force resists
until February, but the situation is hopeless.
MacArthur realises that he simply can't hold out any longer
so he's ordered to abandon the Philippines
and he gets on board a torpedo boat and he turns and waves to people
he's leaving behind, and he says, "I shall return."
He was ordered to leave the Philippine Islands so that we
would not have to face something as the British faced at Singapore,
where you see this well-known general come out
and surrender to the Japanese.
The 11,500 American and 64,000 Filipino soldiers left behind
are rounded up.
Forces that surrender on the Bataan Peninsula then have to be
moved to a prisoner of war holding area at a place
called Camp O'Donnell.
68 miles, and they're forced to cover that distance on foot.
So many prisoners die on the infamous 68 mile walk to
Camp O'Donnell that it becomes known as the Bataan Death March.
The Japanese force thousands to March through these
absolutely appalling conditions and along the way,
they chop off the heads of American officers with samurai swords,
they run bayonets through Filipinos, it's basically murder.
The way is now clear
for the Japanese to assault their key targets.
Once they control Malaya and the Philippines,
the Japanese are now ready to take the Dutch East Indies and Burma.
Now, these are vital for the Japanese
because they are going to get 70% of the world tin,
almost all the world's rubber, and massive oil reserves.
It also opens the way towards Australia, with unexpected results.
That forces Australia to then recall troops that were
committed in the North African desert.
And so the Australians, who are opposing Italians, are pulled
back toward Australia, leaving a vacuum there that emboldens
Axis forces in North Africa.
It's a completely unforeseen consequence of something that
has become a truly global war.
And this is a global war in more ways than one.
As the Americans retreat to lick their wounds,
they've more than just Japan to worry about.
You've got Hitler knocking on the gates of Stalingrad, and you've got
the British massively on the back foot in North Africa,
and what's worse still, for the Allies, is that Hitler's
U-boats are wreaking havoc in the North Atlantic.
Unable to conquer Britain, Hitler decides to starve
her into submission instead.
As an island nation, Britain is 50 million mouths to feed and two
thirds of the food that it uses to feed those mouths comes from abroad.
Britain require at least 23 million tonnes of supplies a year
just to keep alive.
And to continue fighting,
Britain also relies on imported raw materials.
90% of its copper, 90% of her weapons grade bauxite,
and 95% of its vital oil and rubber come mostly from the United States.
But Britain is on the verge of financial collapse.
So in March 1941,
President Roosevelt forces through the Lend-Lease Act...
..a credit lifeline that allows Britain to buy whatever it
needs from the US and pay for it later.
America didn't want Britain to fall to the Nazis
because we were the last bastions of the free world in Europe.
Without American support,
then Britain wouldn't really be able to stay going.
To survive, convoys of Britain's 3,000-strong merchant fleet
constantly traversed the Atlantic.
Protecting them is the British Royal Navy.
But lurking beneath the service is a fleet of dead-eyed
hunters on a mission to destroy them all...
..their submarines...
..Germany's U-boats.
The U-boat itself is capable of intercepting the aid that is
being shipped across the Atlantic,
and potentially even stopping the flow of goods reaching Britain.
If not stopping it entirely, at least slowing it to
a trickle to the point that Britain can be brought to its knees.
Submarine fleet Admiral Karl Donitz calculates that goal requires
600,000 tonnes of Allied shipping to be sunk every month.
He asks Hitler for a fleet of 300 U-boats but gets just 43.
Adolf Hitler underestimates what the U-boat is capable of.
It's his one and only true strategic
weapon during the Second World War and he undercuts it.
He doesn't think they are capable of delivering war winning results,
which they easily could have produced.
But even in small numbers, U-boats are devastating...
..accounting for 70% of ships sunk the German Navy.
There is a sense, I think, in which the U-boat army, which is
very small in 1940, sometimes only a dozen boats at sea,
outperforms its limitations and extracts a huge
toll from British and later on American and Canadian shipping.
U-boats prowl the 600-mile wide mid-Atlantic gap known to
sailors as the black pit because it is out of range of Allied air cover.
Donitz maximises his small fleet's kills by sending them
to hunt in wolf packs.
A wolf pack would operate in coordination with one another.
A group of, say, five U-boats drove a wedge into a convoy.
They separated the faster ships from the slower ships,
and if they could separate the convoy, it was easy hunting.
Wolf packs are devastating...
..sinking a full quarter of British
shipping in the first year of the war.
Then in early 1941, they reached Admiral Donitz' target
of 600,000 tonnes a month and push Britain to breaking point.
They were in a target rich environment and they were,
they were the hunters.
When up to 57 men live for six months in a cramped metal tube
in which they are liable to drown or be blown to smithereens,
unshakeable commitment to their cause is vital.
The average age of the U-boat crewman was 21 years old.
These are young people who had grown-up under Nazi
indoctrination, and so they were raised to do exactly what they were
told and they were raised to put up with quite horrifying conditions.
It was really a floating metal coffin.
75% of U-boat men perished -
among the highest mortality rate of any of the war's armed services.
It's a terrible sacrifice, but for German high command,
it's worth it because the wolf packs are delivering.
For the German sub-mariners, this period was known as the happy
time, it wasn't a happy time for Churchill, he later wrote
about it being the only time in the war where he was genuinely scared.
April 1941.
In the Atlantic Ocean, the British Navy hunts for German U-boats.
But they cannot find them because they don't know where they are.
The German U-boats are guided by messages
which are encrypted in undecipherable codes.
The encrypted codes are produced by Enigma, a machine that can
produce a mind boggling 1,253 trillion code combinations.
Until Enigma is deciphered, Britain risks defeat and even starvation.
To crack the Enigma machine,
all the greatest minds are assembled at Bletchley Park
in Buckinghamshire, including the famous mathematician Alan Turing.
Based in Hut 8 at Bletchley's Government Code
and Cypher School, 29-year-old Turing has his work cut out
because the Germans reset Enigma daily.
These encrypted messages were believed,
by the German regime, to be unbreakable.
The human mind is not capable of running through the potential
settings quickly enough because there are only 24 hours in a day
and the codes change every 24 hours.
So Turing doesn't try to break the code himself.
He envisions something far more powerful than the human brain.
Turing creates a special machine, and this enables him
to analyse thousands of transmissions at a time.
It's really the world's first computer and it's called the Bombe.
What Alan Turing has created is something
so technologically far ahead of its time, and I think that is why
we marvel at its creation, it is just extraordinary.
On April 1st 1941, Bletchley Park first breaks the Enigma code.
Thanks to Turing, more than a million enemy transmissions
are intercepted, laying bare the position of Germany's wolf packs,
around which over 1.2 million tonnes of shipping are re-routed.
Britain's transatlantic lifeline is open.
But it doesn't last long.
Germany's Enigma code gets an upgrade.
The Germans noticed that they haven't intercepted
a convoy for six months or so, so to be on the safe side,
they add an additional rotor to the Enigma.
Enigma code combinations increased 26 times,
to over 32,500 trillion,
a number that even Alan Turing's proto-computer cannot cope with.
For the wolf packs, hunting season is back on.
This Enigma blackout could not have come at a worse time
because the US is about to send lots of people
and lots of equipment across the Atlantic through
the potentially dangerous waters where U-boats are hunting.
In the last six months of 1941,
U-boats sink just over 720,000 tonnes of Allied shipping.
In the first quarter of 1942 alone,
sinkings rise to 2.6 million tonnes, and by year's end,
that figure rises to almost eight million tonnes, and 1,662 ships.
To make matters worse,
the Royal Navy's oil reserves are down to just two months.
The Allies need another breakthrough.
It comes in spectacular fashion...
..in Mediterranean waters off the Egyptian coast.
In October 1942, U-boat 559
is actually hit by HMS Petard
and sunk below the water line.
While it was sinking, three Royal Navy sailors dove overboard,
swam to the U-boat, went aboard it,
rummaged through it as it's sinking,
the U-boat suddenly rolls over, and two of the sailors go down with it,
sacrificing their lives.
But it was vital because the survivor actually pulled
a code book from the U-boat.
And when Turing poured over it back at Bletchley Park,
they were able to break the upgraded Enigma codes.
That sacrifice was so worthwhile because soon thereafter,
Bletchley Park is reading the U-boat mail again.
Over the next year, the Germans sink only 812 ships.
For the loss of 242 submarines.
At the same time, new weapons like the Hedgehog anti-submarine
system and the B24 bomber come online.
The pendulum swings and the hunters become the hunted.
Facing total annihilation, Donitz orders all his U-boats to
withdraw from the North Atlantic on 24th May 1943.
The following month is the first in the whole war in which not
a single convoy is attacked.
That is what turns the tide on the U-boat and from May 1943
until the end of the conflict,
the U-boat is no longer the scourge of the seven seas.
Yet all this will be for naught
if the Soviets cannot win the battle for Russia.
On the banks of the River Volga,
a desperate struggle for survival is being fought out
in a nondescript city whose name will echo through history...
..Stalingrad.