Kilroy Was Here

Kilroy was here is an American popular culture expression that became popular during World War II; it is typically seen in graffiti. Its origins are debated, but the phrase and the distinctive accompanying doodle—a bald-headed man (possibly with a few hairs) with a prominent nose peeking over a wall with the fingers of each hand clutching the wall—became associated with GIs in the 1940s.

In Britain, the graffito is known as "Mr Chad" or just "Chad", and the Australian equivalent to the phrase is "Foo was here". "Foo was here" might date from World War I, and the character of Chad may have derived from a British cartoonist in 1938, possibly pre-dating "Kilroy was here". Etymologist Dave Wilton says, "Some time during the war, Chad and Kilroy met, and in the spirit of Allied unity merged, with the British drawing appearing over the American phrase." "Foo was here" became popular amongst Australian schoolchildren of post-war generations. Other names for the character include Smoe, Clem, Flywheel, Private Snoops, Overby, The Jeep, and Sapo.

Author Charles Panati says that in the United States "the mischievous face and the phrase became a national joke... The outrageousness of the graffiti was not so much what it said, but where it turned up." The major Kilroy graffiti fad ended in the 1950s, but today people all over the world still scribble the character and "Kilroy was here" in schools, trains, and other similar public areas.