I've been looking for this and I can't seem to find a concrete answer, though I was able to note that it was a thing the British Armed Forces did in World War II. What was this practice?
Assuming you're not talking about trash-talking between pubs and regiments on Mount and Blade: Warband I'll assume you're talking about the practice of forced bathing often imposed upon lower-ranking members of a fighting unit circa WW2. A "bath book" was kept to keep track of who was regularly washing. A soldier who slacked off on personal hygiene ran the rish of being pinned to the ground by squad-mates, stripped naked and scrubbed with a broom. It was intended as a form of unofficial punishment within Non-commissioned ranks. Have a nice day :D
Source: http://www.bbc.co.uk/history/ww2peopleswar/stories/59/a6006359.shtml