With the outbreak of World War I, De Wet enlisted in the Freikorps on September 9, 1914 in Windhoek, hoping among other things to free his homeland South Africa from British rule. Although the local Freikorps were short-lived, there was no comparable unit in any other German colonies. The all-volunteer corps was recruited from the already large Afrikaner population. The Freikorps's goal was to support the Maritz rebellion that arose after the Union government sided with Great Britain at the outbreak of war in August 1914. The rebels strongly opposed the Union Defense Force (UDF) invasion of German South West Africa and saw British forces' diversion to other fields by the broader war as an opportunity to restore the independence of the Boer republics.