I saw this film on TV in France many years ago (likely late 80s). I’m positive it was dubbed from English to French. It was in monochrome, not colour. The scene I recall is near the end, with monks marching into stalls (in a chapel?) and then throwing off their robes and revealing themselves to be knights, possibly with the King present. I thought it was Ivanhoe or Quentin Durward, but the plots of neither ring any bells with regard to that scene, and both of those are in colour.
Help me Dopers!