How I Won the War is a 1967 British black comedy film starring Michael Crawford, Jack MacGowran, Roy Kinnear, Lee Montague, and John Lennon in his only non-musical acting role. The film, which was directed and produced by Richard Lester, is based upon the 1963 novel of the same name by Patrick Ryan.

The film uses a variety of styles such as vignettes, straight-to-camera, and docu-drama to tell the tale of the fictional 3rd Troop, the 4th Musketeers and their misadventures through the Second World War. The screenplay takes a comic and absurdist attitude towards the conflict through the Western Desert Campaign in mid-late 1942 to the crossing of the last intact bridge on the Rhine at Remagen in early 1945.