Hungary–Romania relations
During World War II, Hungary and Romania became allies and participated in the war against the Soviet Union. But after the coup on 23 August 1944 Romania switched sides and fought against Hungary. Consequently, Soviet and Romanian troops invaded Hungary, occupied Northern Transylvania by October 1944 and re-established the Romanian administration in the region in March 1945. The 1947 Treaty of Paris reaffirmed the borders between Romania and Hungary as originally defined in Treaty of Trianon 27 years earlier, thus confirming the return of Northern Transylvania to Romania.
Leopold Steinbatz
World War II in Europe had begun on Friday, 1 September 1939, when German forces invaded Poland. Steinbatz was transferred to 2. "Staffel" (6th squadron) of the "Ergänzungsgruppe" of "Jagdgeschwader" 52 (JG 52—52nd Fighter Wing), a supplementary and training fighter group of JG 52. There he first met Hermann Graf, his future wingman on the Eastern Front. In August 1940, Steinbatz was transferred to 9. "Staffel" (9th squadron) of JG 52, a squadron of III. "Gruppe" (3rd Group) and was then assigned to the "Luftwaffenmission Rumänien" ("Luftwaffe" Mission Romania) under the command of "Generalleutnant" Wilhelm Speidel. The military mission from Germany supported General Ion Antonescu in the reorganization of his country's armed forces. III./JG 52 was transferred to Bucharest in mid-October and temporarily renamed I./"Jagdgeschwader" 28 (I./JG 28) until 4 January 1941.