Kampfgeschwader 53 "Legion Condor" (KG 53; English: Condor Legion) was a Luftwaffe bomber wing during World War II.Its units participated on all of the fronts in the European Theatre until it was disbanded in May 1945. At all times it operated the German bomber type Heinkel He 111. Only the 15th (kroat) Squadron of KG 53 (15.(kroat)/KG 53), established in Agram (Zagreb) July 1942, operated the Dornier Do 17 Z.