How I Won the War 1967
Dir. Richard Lester
Starring: John Lennon, Michael Crawford
A rather daring film to make at the time, it criticizes the Vietnam War by using WWII, much in the way M*A*S*H used the Korean War. A veteran (Crawford) is rather inaccurately reminiscing about his adventures in North Africa during the war.
There is some speculation that the line "I saw a film today, oh boy/The English army had just won the war" from "A Day in the Life" on Sgt. Pepper is Lennon referencing the film he co-starred in.
Lester is also the director of A Hard Day's Night, and Help!, among others. Though considered a British director, he was actually born in my hometown, Philly.