Under the terms of the Treaty of Versailles, the German Army was unable to grow to more than 100,000 men. One way that Adolf Hitler dealt with this issue was to allow the Sturm Abteilung (SA) to grow rapidly. By 1934 the SA had grown to a force of over 4,500,000 men.
The growth in the importance of the SA worried other leaders in the National Socialist German Workers Party. It also upset leaders of the German Army who feared that it would be taken over by the Ernst Roehm and the SA. They were won over to the Nazis when Adolf Hitler ordered the Night of the Long Knives where around 400 leaders of the SA were murdered.
Whereas the SA now lost its power, Hitler allowed the German Army to grow rapidly. In 1935 he introduced military conscription. This enabled the German Army to train 300,000 conscripts a year. By 1938 it had 36 infantry divisions of 600,000 men.
In 1939 the German Army had 98 divisions available for the invasion of Poland. Although some were ill-equipped veteran reservists, the still had 1.5 million well-trained men available for action. It also had 9 panzer divisions. Each one had 328 tanks, 8 support battalions and 6 artillery batteries.
When the German Army mounted its Western Offensive in 1940, it had had 2.5 million men and 2,500 tanks. Whereas the French Army had the ability to mobilize 5 million men, the army supported by motorized infantry units and aircraft easily secured victory.
The German Army continued to grow and in June 1941 around 3 million (including 200,000 from its allies) were available for Operation Barbarossa against the Soviet Union. This included 142 infantry divisions, 17 panzer divisions and 4,000 tanks.
Despite heavy losses in the Soviet Union and in France following the D-Day landings, the German Army had 168 infantry divisions and 25 panzer divisions by January, 1945. The Waffen SS also had 23 divisions, seven of which were armoured.
The army was also supported by a People's Militia created by Adolf Hitler to defend German cities under attack from the Red Army. This was mainly composed of men too old or too young for regular service. It was also poorly equipped as the German economy found it increasingly difficult to fully support the needs of its armed forces.
Of the seventeen field marshals in the German Army, ten were relieved of their commands by the Fuehrer in the course of the war, three were killed after the July Plot, two were killed in action, one was taken prisoner and only one remained throughout the war without being subject to discipline.
Of thirty-six generals, twenty-six were removed from their post, of whom three were executed and two were dishonorably discharged; seven were killed in action and only three remained in service throughout the war without disciplinary action.
A total of around 12.5 million Germans served in the army during the Second World War. It is estimated that of these, between 3 and 3.5 million were killed.