Preparations for War

How well prepared for war was France in 1939?

The French army numbered in the region of 900,000 men in 1939. In addition to this number of enlisted men, the French had 5 million reservists who had received some military training.

France had long prepared for a possible invasion by German forces. Having seen German troops attack with considerable success in 1870 and 1914 they had, in the post first world war era, developed a large and supposedly impregnable line of defenses. These defenses incorporated the Maginot line, the natural features of the Ardennes Forest and the deployment of troops in prepared emplacements along the border with Belgium.

The Maginot Line

The Maginot Line was an impressive series of defensive bunkers, emplacements and tank traps stretching from the French border with Switzerland along the border with Germany up to the Ardennes forest.

Cut deep into the rock, the defenses here were designed to prevent tank movement across the border. The bunkers were highly reinforced and would not be penetrated by bombardment by the Luftwaffe and incorporated automatic weapons that would make a frontal assault by infantry suicidal.

In 1939 / 1940 the French strategists believed that the only attack options available to the German forces were to attack the Maginot line, or to invade via Belgium as had happened in 1914.

To this end the forces were deployed in two sectors. A large number of men stood guard in and around the Maginot line whilst the remainder of the French force was positioned to the North of France in defensive positions close to the Belgian border.

Limited forces were deployed in the region of the Ardennes Forest as the strategists believed that thickness of the trees along with the semi mountainous terrain made the area too difficult for a coordinated assault involving tanks.

The French reserve was positioned towards the North, with the intention of moving up to support troops facing German forces along the Belgian border.


The French Air Force consisted of 826 fighters and 250 bombers at the outbreak of war. This followed a move to increase the number of fighters available made by the French Government in 1938. This force was supported by 350 planes of the RAF that were sent to aid France in the event of war with Germany. Sorties flown against the Luftwaffe prior to the German invasion of France saw the number of operational fighter planes available reduced to 740.


Spartacus - The Spartacus site offers information about the size of French forces, explains how the French chose to defend themselves in 1940 and explains the German tactics when they did invade France.

In the Shadow of the Maginot Line - an analysis of the Allied defense of France.

France's defeat in the 1940 campaign - a detailed academic account of the reasons for the defeat of the French and British forces defending France in 1940.

1939 - This page outlines the French strategy and the way that the German forces exploited its weaknesses.

The Maginot Line - a virtual tour of the Maginot Line. Available in French or English.