When the Roman Empire split in the 4th century AD into the Western and Eastern empires, the boundary between the two stretched from the Montenegrin coast up the river Drina to the confluence of the Slava and the Danube and then further north. This boundary has remained virtually unchanged for 1500 years: the European, Catholic west and the Orthodox east meet on Slav territory. With Croatia having become an independent state in the 1990s, this text traces the history of the region and its people. It is divided into major sections on: the early medieval Croatian state (until 1101); the periods of union with Hungary (1102-1526) and with Austria (1526-1918); incorporation in Yugoslavia (1918-91); and the creation of a sovereign state.