How Weimar Germany Prepared the Way for the Fall of France

History is full of ironies. One of the greatest is the effect that the Treaty of Versailles had on causing and shaping the next World War.

The usual narrative tells you that the harsh economic conditions imposed on Germany by this treaty played a vital role in propelling Hitler to power and thus causing the war. This is partly true, but more interesting than this is how the Treaty's military conditions, designed to secure the safety of France and other countries, instead had an enormous impact on the subsequent war and more or less directly led to the military humiliation of France in 1940.

How this happened is an interesting tale.

By the terms of the Treaty of Versailles, the French first of all regained the provinces of Alsace and Lorraine lost in the 1870 Franco-Prussian War. This gave them a solid and defensible frontier on the Rhine. In addition to this, the part of Germany that was West of the Rhine was demilitarised, and the German army limited to a mere 100,000 officers and men.

France and its allies contain Weimar Germany

This put Germany in an awkward position, because this comparatively small force had to defend a long frontier -- approximately 3,000 miles long -- very little of which was naturally defensible.

During the 1920s and early 1930s, the French army was at least three times bigger than the German army. It had 58,000 professional soldiers (officers, NCOs, and specialists), 45,000 North African natives garrisoned in France, and around 215,000 young men doing their annual military service. This force of 318,000 had to defend about 1,700 miles of border, but, of that, around 1,000 miles was mountainous border and therefore relatively easy to defend.

For the French, a strategy of static defence made excellent sense. But for the Germans, with their much longer and less mountainous borders and their much smaller army, a strategy of static defence made no sense at all. It was thanks to this worrying reality that the German High Command was much more open to the ideas of mobile warfare and willing to listen to the ideas of officers like Heinz Guderian, who was a disciple of the theories of the British military thinkers JFC Fuller and Basil Liddell-Hart.

Heinz Guderian

Writing in his autobiography Panzer Leader, Guderian describes the problem of German defence in the Weimar period and how this pushed the German army towards developing mobile warfare:

During the First World War there had been very many examples of the transport of troops by motorised vehicles.  Such troop movements had always taken place behind a more or less static front line;  they had never been used directly against the enemy in a war of movement. Germany now was undefended,  and it therefore seemed improbable that any new war would start in the form of positional warfare behind fixed fronts. We must rely on mobile defence in the event of war. The problem of the transport of motorised troops in mobile warfare soon raised the question of the protection of such transports. This could only be satisfactorily provided by armoured vehicles. I therefore looked for precedents from which I might learn about the experiments that had been made with armoured vehicles.

So, while the situation of the French pushed them towards the idea of static defence and an essentially conservative outlook that resulted in their over-reliance on the 'great white elephant' of the Maginot Line, the situation that the Germans faced forced them to think outside the box and adopt ideas and attitudes that they would never have chosen otherwise.

If Germany had been allowed a much larger army, no doubt they would have largely mirrored the French system. But the small army they were allowed could only be effective by being a lot more mobile. 

By the time that Hitler came to power in 1933 with the intention of greatly expanding the 100,000-man German army to millions, the DNA of the mobile warfare that was to crush the French in 1940 had already become established. But, ironically, this was much more the legacy of the understrength Weimar Republic army than the militaristic regime of Hitler.