Duchy of Saint Sava

The Duchy of Saint Sava was a late medieval polity in southeastern Europe that existed from 1448 until 1482, when it was absorbed by the Ottoman Empire. It was founded and controlled by the Kosaca noble family, whose head, Stjepan Vukcic Kosaca, began styling himself Herceg of Saint Sava in the autumn of 1448, after Saint Sava, whose relics lay in the Mileseva monastery within his domains. The title later gave the region the name Herzegovina. At its height the duchy covered southern parts of modern Bosnia and Herzegovina and extended into coastal Croatia, northwestern Montenegro and southwestern Serbia. Stjepan allied with Alfonso V of Aragon and Naples and fought the Bosnian crown, the Republic of Ragusa and the Ottomans. After the Ottoman conquest of Bosnia in 1463, most of the duchy's eastern lands were lost by 1465. Stjepan died in 1466 and his sons Vladislav and Vlatko divided what remained. Reduced to the area around Novi, the duchy fell when the Ottomans took that fortress in late 1481 or early 1482.