The name Sennelager literally translates as "camp on the Senne" - a name originating in 1851 when the Prussians used the area as a training camp for their cavalry.
During the First World War (1914-1918) a POW camp here housed merchant seamen, most notably many British trawlermen taken prisoner after German raiders sank their ships in the North Sea, especially in the first days of the war.