"Jerry was used by the British in the Great War as a nickname for the Germans. One possible origin is that Jerry was thought to be a common name among Germans, like 'John' with Americans. Another, and perhaps the true origin, is that bed pans/chamber pots were called Jerries, and the Germans helmets looked like them, so... Jerry was one of many nicknames used to call the Germans, the French preferred Boche, the Americans, Krauts. Another common one was 'Hun'. The usage of Jerry, and the rest, although I can't say I have seem much use of Boche outside of WW I related things, continued during the Second World War. The gas/water container used by the Germans in WW II was nicknamed a Jerry can. During the Great War, the Germans, when talking to the Englishmen in the opposite trenches, would use Tommy to reference them, while the British, of course, used Jerry in regard to the Germans." [i]:O[/i]