Region of E Croatia bounded by the Sava, Drava, and Danube rivers; Osijek is the largest town. E and W Slavonia declared themselves autonomous provinces of Serbia following Croatia's declaration of independence from Yugoslavia 1991, and the region was the scene of fierce fighting between Croatian forces and Serb-dominated Yugoslav federal troops 1991–92. After the cease-fire 1992, 10,000 UN troops were deployed in E and W Slavonia and contested Krajina.