"In the Balkans, too, there were multiple civil wars along ethnic, religious and ideological lines [during World War II]. Yugoslavia had fallen apart in the wake of the German invasion of April 1941. Seizing the moment, the Croatian leader Ante Pavelic had pledged to side with Hitler. In the ensuing chaos, his Ustasas waged a brutal campaign of ethnic cleansing against their Serbian neighbours in Croatia and Bosnia-Hercegovina, torturing and killing hundreds of thousands of them. The populations of entire villages were packed into their churches and burned to death, or were transported to be murdered at camps like Jasenovac. Serbian Cetniks and Partisans repaid these crimes in kind. Of the million or so people who died in Yugoslavia during the war, most were killed by other Yugoslavs. This included nearly all of Bosnia's 14,000 Jews. In Greece the German occupation was the cue for bitter conflict. There, as in Yugoslavia, a three-cornered war raged - between the foreign invaders and nationalists, but also between nationalists and indigenous Communists. When Bulgaria annexed southern Dobruja from Romania, tens of thousands of people were expelled from their homes on either side of the new border."