How Hitler did the impossible

In 1940, Hitler did the seemingly impossible. Within a matter of weeks, Germany had managed to take the entirety of France and send the British army back across the channel. This remarkable success was widely put down to their new tactic: Blitzkrieg or 'Lightning War'. So, what is Blitzkrieg and why was it so effective?

Dunkirk 1940, the British Army is in ruins. Hundreds of thousands of men scramble to escape from France, as the Luftwaffe swirls overhead. It is chaos.

Just two weeks after Germany had launched their invasion of France the writing was on the wall, evacuation the only chance of survival. The Germans had advanced with terrifying speed covering over a hundred and twenty miles in just five days. The Allies plans had unraveled before them at the hands of a numerically smaller enemy. Suddenly a new word appeared in the British press: Blitzkrieg -  Lightning War. So what is Blitzkrieg? And why was it so successful?

The main principle of Blitzkrieg is to win by not fighting.

That's John Delaney, head of the Second World War team at Imperial War Museums. Now what he said might sound impossible, but in practice it was very effective.

You identify the weak point in the enemy's line, break through, and cause disruption in the enemy's rear areas. So you defeat them by dislocation, not destruction on the battlefield.

Despite their inferior numbers Blitzkrieg made it possible for Germany to rapidly defeat its foes and achieve victoriesthat were inconceivable just weeks before, but to find out why we have to go all the way back to the First World War and the genesis of Blitzkrieg.

The ideas behind Blitzkrieg are generated in the First World War when all the sides are looking for ways to break the trench deadlock. The idea of reestablishing fast-moving warfare is of real importance to Germany because the Versailles Treaty, the treaty that comes into force at the end of the war, limits the German army to a maximum size of a hundred thousand men, which means that they have ten divisions which is a tiny amount if you compare that to
the French army of the time which is about eighty five divisions strong. So by necessity they have to come up with new ways of thinking new ways of fighting war, they can't go back to the you traditional First World War because they simply haven't got the men.

So blitzkrieg then is born of necessity, Germany has to make do with less. But their small army wasn't the only problem, they also had to find new ways to train.

So the the Spanish Civil War which was fought in the mid 1930s, the Germans became heavily involved in and actually sent a legion to fight on Franco's side, to learn how to fight a real war by fighting a real war.

They also trained with cardboard versions of their Panzer tanks because they weren't allowed to have real ones.

They trained everybody who was in the German army up to the next rank within the army, so all NCOs were trained as officers, all junior officers are trained as staff officers. Principally what it means for Germany is that when Adolf Hitler comes into power in 1933 there's a small force that can be rapidly expanded into a highly professional mobile army ready to fight a Blitzkrieg war.

So with their preparation now complete Germany was ready to attack, so how did they do it? Well, according to John you need three things to achieve a successful Blitzkrieg. First up, speed of movement.

The whole point of blitzkrieg is to keep moving, don't stop, because if you stop you get entangled in a battle of attrition. Keep moving, always look for the weak point in the enemy line.

Contrary to popular belief only about 15 percent of the German army was actually mechanised, concentrated at the very tip of the spear. That mean that even if Germany was outnumbered overall, at the point of attack, she always exceeded her
enemies.

And then the Luftwaffe, their kit is tailored very specifically to supporting the armed forces on the ground. So the Panzers at the front could call them up and ask pin-point air support from the Luftwaffe's aerial artillery to help them break through the line.

And that brings us to number two, the speed of communications and decision making.

The main point is to find this weak point in the Allied line and apply as maximum mechanised pressure you can to that and break through into the rear areas. You need to be able to act flexibly, quickly, and change the axis of your attack extremely quickly so German junior commanders could make very big decisions. Perhaps they've been told to attack down a particular axis towards a hill or something and they could see that that was really well defended. They had the opportunity to say 'I'm not going in that direction we're going to get bogged down over there to our right flank that seems to be much less well defended we're turning right we're going that direction it'll will break through much quicker'. I mean these these are decisions that are made in minutes whereas French command decisions would
take days.

And speaking of the Allies the final part is an overconfident enemy. So the Allied armies were geared up to fight the First World War all over again. They've won the last time round so in their mindset why change? You know if it ain't broke don't fix it. So they're geared up to fight a static defensive oriented war, they're not investing in things like radio communication to enable quick snap decisions to be made near the frontline.

Their main a method of communication is to laid telephone lines as it was in the First World War. All you have to do with a telephone line is cut it and then you can't communicate. They were paralyzed, there's just indecision everywhere throughout the command structure of the French and British armies.

Put all of that together and it really worked. While the regular German infantry took on the Allies in Belgium and the Netherlands, that armored spear tip found the Allied weak point in the Ardennes and rushed through it. Encircling their enemy and causing mayhem and destruction at every turn. Once the British had evacuated at Dunkirk, Germany turned south taking in weeks what they had never managed during the whole First World War. By mid-June they were in Paris and by the end of the month the French had signed their humiliating surrender in the same railway carriage as Germany in 1918. But hang on a minute. If blitzkrieg is so powerful then why didn't Germany keep using it and win the war?

So what you what you need to do as the Allies to defeat Blitzkrieg is stay in the war. The Allies, really what they want to do is turn it from this fast-moving Blitzkrieg war into a war of attrition, a war production - literally out producing your enemy.

Archive Clip: "Speed is vital in battle and therefore equally vital is supply. If there's another M in war it is mass. The fighting men on landand in the air need masses of everything."

So this is why Churchill is extraordinarily keen to bring America into the war as soon as possible so he can bring in the American military muscle.

Archive Clip: "Bombs, bombs a multitude of beautiful bombs ready to be delivered just where they hurt most."

So if you're fighting a war of production it doesn't matter if you lose the initial battles because you know, in the end, as long as you can hang in there in the end you will out produce the enemy and overpower them just by sheer weight of numbers.

But blitzkrieg wasn't quite dead yet, it was successfully used against the Soviet Union in 1941 who failed to heed to many of the warnings they could have gathered from the Battle of France. But once the Second World War became that war of production and a defensive one for the Germans Blitzkrieg was a far less useful tactic. Despite a late attempt at the Battle of the Bulge in 1944, Blitzkrieg could not save Germany from her ultimate defeat in 1945.

So those factors that make Blitzkrieg a necessary strategy and proved so successful in the early part of the war. Once the Allies have learned what they are and can counter them the Germans have got losing hand, there's nothing else they can do except slowly slowly lose the war.

Find out more

A large ship steaming on a calm sea with small aeroplanes flying in the sky above. The sun shines down from the top left corner of the composition, casting a path of bright rays down onto the sea. In the distance another ship can be seen sailing on the horizon.
HMS Glorious in the Arctic, 1940, by Eric Ravilious.
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