The line comes from Monty Python and the Holy Grail (1975), spoken by the Black Knight, played by John Cleese, during his absurd duel with King Arthur. After losing both arms and legs, he keeps insisting he can still fight, and 'just a flesh wound' became the scene's most quoted line. It lived on through VHS, DVD and early internet forums before becoming a staple reaction meme, GIF caption and soundboard clip. Creators still use it because the image of cheerful denial fits almost any minor disaster.