Ancient Romans used pigeons to tell owners how they placed in chariot racing. Genghis Khan made pigeon relay posts in Asia and Eastern Europe. But it was during the Siege of Paris in 1870 carrier pigeons were recognized. As the Prussians advanced, putting notes in metal balls and sending them down the river was not working. Six days after the bombing began, a hot air balloon named La Ville de Florence released 3 pigeons on Sep. 19, 1870 at 11 a.m. The pigeons got back at 5 p.m., mission accomplished.