In the century of nationalism, the House of Habsburg ruled over a vast territory in East Central Europe. Second only to Russia in size on the European continent, the Habsburg lands stretched from the Alps to the foothills of the eastern Carpathians and from the shores of the Adriatic to the Sudetes mountain range on the border with Saxony. The core of this territory in the Alps, corresponding roughly to what is today Austria and Slovenia, had been ruled by the Habsburgs from the High Middle Ages. In 1526, the Habsburgs made a decisive step to become East Central Europe’s leading power by acquiring the Bohemian and the Hungarian crowns. After one and a half centuries of warfare against the Ottoman Empire, the long eighteenth century witnessed the Habsburgs’ decisive eastern expansion. First, at the turn of the seventeenth and eighteenth centuries, they reconquered central Hungary and Transylvania from the Ottomans.

The Black Sea, Russia, and eastern Europe exported slaves throughout the medieval period. Most had been born free but were enslaved through capture or occasionally through sale by relatives. During the eighth through tenth centuries, slaves were traded from eastern Europe and the Baltic to elite households in Byzantium and the Islamic world via the Dniepr and Volga river systems, the Carolingian empire, and Venice. In the thirteenth century, the structure of this slave trade changed as a result of the Mongol invasion of eastern Europe, Italian colonization of the Black Sea, the success of the Mamluk state, and the crusading activities of the Teutonic Knights in the Baltic. People enslaved in the Baltic now tended to be traded westward rather than eastward; people enslaved in eastern Europe and the Caucasus tended to pass through the Black Sea into Italian, Mamluk, or Ottoman hands; and people enslaved in the Balkans were trafficked primarily by Venetians or Ottomans. Many aspects of this trade deserve further study, however, such as political marginality and decentralization as factors that enabled slaving; violations of the principle that slaves should come from a different religious background than their owners; and the logistics of local slave trades.

From the late fourth century onwards, Christendom was assailed by a succession of invaders. The first wave consisted of Germanic tribes – Visigoths, Ostrogoths, and Vandals – and their irruptions brought down the West Roman Empire. During the sixth century, Slavonic groups emerged in the territory north of the Danube that the Germanic tribes had evacuated and began incursions into the South-East European lands of the Byzantine empire. In the late ninth century, the old Roman province of Pannonia together with the Hungarian Great Plain was occupied by the Magyars, a Finno-Ugrian group, originally from Siberia, that had over the preceding centuries made its home on the western steppes. The Magyar settlement destroyed several nascent Slavonic principalities and was accompanied by extensive raids into the Balkans and Western Europe.