Why the German
invasion of Russia
failed.

The largest army ever sent into battle.
And six months later, it was finished.

On 22 June 1941, 3.8 million Axis soldiers stepped across the Soviet border at the same time. The front was 1,800 miles long. Nobody had ever launched an invasion this big. Nobody has since.

Six months later, that same army — the best-trained, best-equipped, most feared military in the world — was stuck outside Moscow, freezing in summer uniforms, fighting a winter battle they hadn't packed for. Within four years, they'd lost the war entirely.

Now, this is one of those stories where everyone knows roughly what happened, but very few people know why. Once you see the reasons — and there are really only four — you'll also understand how the Second World War actually ended, how Russia became a superpower, and what happens to even the best army in the world when geography and supply lines turn against it.

The plan was: eight weeks, and done.

The German army had just done something extraordinary in 1940 — they'd taken France in six weeks. Six weeks! Nobody had managed that before. Their formula was simple: fast tanks, encircle the enemy's main force, strike decisive blows, watch the whole structure fall apart. It had worked beautifully in France. They figured it would work in Russia too. Eight weeks, give or take. Done before winter.

They split their army into three groups. Army Group North headed for Leningrad. Army Group Centre, for Moscow. Army Group South, into Ukraine. The expectation: hit the Red Army hard enough at the start, and the whole Soviet system would crack the same way France had. A house of cards, basically.

1,800 miles long.

Now, let me give you a sense of how big this front actually was. 1,800 miles. From the Baltic Sea down to the Black Sea. For comparison, the D-Day landings — the famous one, three years later — happened on a beach about 50 miles wide. The Eastern Front was 36 times bigger.

Here's something that doesn't fit the popular picture. When you imagine the German army of 1941, you probably picture columns of Panzer tanks rolling across the steppe. They had tanks, yes — 3,500 of them. They also had 600,000 horses, and most of their soldiers walked. The Wehrmacht of 1941 was a horse-and-foot army with some tanks bolted on the front. This matters enormously — we'll come back to it.

At first, it looked like the plan was working.

For the first three months, it looked like Germany had been right. The Wehrmacht advanced 300 miles in three weeks. Three giant encirclement battles — Minsk in July, Smolensk in August, Kiev in September — captured Soviet soldiers in numbers that are almost hard to believe.

By the end of September, the Germans had taken roughly 3 million Soviet prisoners. Let me put that in perspective: that's bigger than the entire pre-war French Army. Captured. In three months.

By any normal measure, that should have ended the war. Every country in history that has lost 3 million soldiers in 3 months has collapsed. And here's the strange thing — Russia did not. And that's where the story really begins.

Kiev cost a month. Moscow needed that month.

In late August 1941, the army aimed at Moscow — Army Group Centre — was ready to strike. Moscow was 200 miles away. Their tanks were fuelled. Their soldiers were rested. They were ready to go.

Hitler said no. Not yet. He pulled the main tank force south, into Ukraine, to help encircle the city of Kiev. His own generals — Guderian, Halder, men who'd been winning battles their whole lives — protested. Hitler overruled them.

Now, here's the thing about that decision. As a tactical move, it worked beautifully. Kiev fell. 600,000 Soviet prisoners. A truly enormous catch. As a strategic move, it was a catastrophe. It cost five weeks.

Five weeks doesn't sound like much. Five weeks in a Russian autumn is the difference between fighting a summer war and fighting a winter war. The Germans were about to find out exactly what that means.

For three weeks, the army drowned in mud.

Russian has a specific word for what happens to roads when autumn rain hits the steppe. The word is rasputitsa, and it means, roughly, the time of mud. Now I have to tell you what "mud" means here, because "mud" is doing a lot of work in that sentence.

The Germans' supply system depended on dirt roads — they carried about 80% of everything the army ate, drove, fired, or wore. In a Russian autumn, those roads turn into something more like wet concrete that swallows things. Tanks sink to their turrets. Horses break their legs trying to pull through. Trucks just stop and stay stopped.

For three weeks in October 1941, the German army moved almost nothing. The window to take Moscow before winter — already too narrow because of Kiev — closed.

In a war planned to last 8 weeks, three weeks of doing nothing is the difference between winning and losing. The Germans had now lost both.

−40°, in summer uniforms.

In December 1941, the temperature in the Moscow region dropped to −40°. That's the one temperature where Fahrenheit and Celsius agree, so it doesn't matter which one you use. Either way, it's very cold.

The German soldiers were still wearing summer uniforms. Why? Because the war was supposed to be over by autumn. The German high command had refused to order winter clothing, because to order winter clothing would have been to admit that the plan might not work. So they didn't order any. Imagine that decision.

What happens when you try to fight a war at −40° in summer uniforms? Tank engines freeze and won't start. Lubricants turn into something like jelly. Rifle bolts seize up. Soldiers get frostbite just standing in line for hot soup.

In the first winter of the war alone, the German army took more than 100,000 frostbite casualties. A hundred thousand men. Many of them lost fingers, toes, hands permanently. Without anyone firing a shot at them. That's what the cold did.

The further they went,
the weaker they got.

Now I want to tell you two things about the Eastern Front that almost nobody mentions, and they both matter enormously.

First. Russian railway tracks were a different width than European tracks. A different gauge. So when the Germans captured a stretch of Russian railway, they couldn't run a German train on it — the wheels didn't fit. Every single mile of captured track had to be physically pulled up and relaid before any German supply train could use it. The pace of the German supply system was not set by their famous Panzer divisions. It was set by railway engineering crews, working with shovels and rails, day after day, mile after mile.

Second. Every soldier you put at the front needs several soldiers behind him. Someone has to bring his food. Someone has to bring his fuel. His ammunition. His boots. His replacement equipment. The further your front line gets from your home base, the longer that supply line stretches, the more soldiers have to be back there moving things forward, and the thinner your actual fighting force becomes.

Here's the counterintuitive thing. By the time the German army reached Moscow's doorstep, it was — astonishingly — weaker than it had been when it crossed the Soviet border five months earlier. The advance had eaten the army. They had burned themselves marching 600 miles.

December 5, 1941. The myth breaks.

Through the autumn, Stalin had been holding back his best armies — the Soviet Far Eastern divisions, sitting in Siberia in case Japan attacked from Manchuria. Then in October, a Soviet spy in Tokyo named Richard Sorge sent back information that Japan would not be attacking north. They were going south, for the British and American colonies. Pearl Harbor was coming.

Stalin moved those Siberian armies west. Fresh troops. Trained for winter. Equipped properly. Forty divisions, give or take.

On December 5, 1941, with German troops 15 miles from the Kremlin — close enough to see Moscow on a clear day — those Siberian divisions hit them. The Wehrmacht was out of fuel, frozen half to death, exhausted. The line cracked. They were driven back 100 miles in a month.

That was the Battle of Moscow. The first strategic defeat the German Army had ever suffered in the Second World War. The myth of the invincible Wehrmacht — the myth that had taken France in six weeks, that had rolled over Poland and Norway and the Low Countries — that myth died in the snow outside Moscow.

The Eastern Front went on for another four years. None of those years went better for Germany than 1941.