The Monroe Bomb was a propaganda leaflet distribution device dropped from Allied heavy bombers. Named after it inventor: Capt. James Monroe during World War II. Thousands of pieces of leaflets with messages in whatever languages were spoken below were inserted into a laminated paper cylinder with a detonator and a delay, and then loaded into a B-17.
The Monroe Bomb exploded at low altitude and let fly leaflets over enemy territory. The Air Force quickly developed more advanced versions of the same idea. For many years, their standard leaflet bomb was the M129, a fiberglass case that holds tens of thousands of flyers. According to a quarterly magazine called The Falling Leaf, the practice of distributing aerial leaflet propaganda goes back to the early 19thcentury. The French used balloons to drop leaflets on the Prussians in 1870. Since then leaflet distribution was tried by other means as well, projecting them in a canister fired from artillery guns.