The announcement of general mobilization on 28 August 1939 brought the entire armed forces on a war footing. All those of draft age from the year 1924 up to and including 1939 were called up. In this way the army reached a total strength of 280,000 men. Rood fulfilled his military service in the Central National Warehouse of Military Clothing and Equipment on Conradstraat in Amsterdam, where he made military uniforms.