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.
History of the Jews in Romania
On the current territory of Romania, between 290,000 and 360,000 Romanian Jews survived World War II (355,972 persons, according to statistics from the end of the war). During the communist regime in Romania, there was a mass emigration to Israel, and in 1987, only 23,000 Jews lived in Romania.