Military

Corps

A formation usually of two or three divisions, with its own artillery and services, numbering several tens of thousands of men. Several corps made up an army.

The corps as a permanent grouping of several divisions was popularised by Napoleon. In the continental armies of 1914 it was also a territorial unit: in peacetime each corps had its own district, from which it drew recruits and reservists. Poles from the Prussian partition served in, among others, V Corps from Poznań and XVII Corps from Danzig, and those from Galicia in the Austro-Hungarian I (Kraków), X (Przemyśl) and XI (Lviv) Corps. On mobilisation Germany also formed reserve corps.

During the war the make-up of corps became fluid. The British and French moved divisions between corps as needed, and a corps became more of a headquarters running a sector of the front. The exception was the Canadian Corps, with a fixed four divisions. The word was also used for formations of a different kind, such as the British Expeditionary Force or the Polish corps raised in Russia in 1917–1918.