Osijek (Hungarian Eszek), city, eastern Croatia, on the Drava (Drau) River. Osijek is a port and an industrial center with oil refineries, flour and sugar mills, and factories producing chemicals, furniture, textiles, and matches. The chief city of the historical region of Slavonia, Osijek was built on the site of an ancient Roman colony called Mursa. It was first called Osijek in the 12th century. Population (1991) 104,761.
