Duke of Transylvania

The Duke of Transylvania (Hungarian: erdélyi herceg; Latin: dux Transylvaniae) was a title of nobility four times granted to a son or a brother of the Hungarian monarch. The dukes of the first and second creations, Béla (1226–1235) and Stephen (1257–1258 or 1259, 1260–1270) of the Árpád dynasty were in fact viceroys with significant authority in Transylvania. The duke of the third creation, Louis, did not administer the province. The fourth duke, Stephen of the Anjou dynasty (1350–1351) did not play any significant role in politics.

Transylvania was an eastern "borderland" (Florin Curta) of the medieval Kingdom of Hungary from the early 11th century. Exposed to attacks by the Cumans and other neighboring nomadic tribes, a high-ranking official especially assigned to this task by the monarch, styled voivode administered the province from the last decades of the 12th century. Transylvania experienced a steady demographic growth from the 1150s, to which the immigration of new settlers from Western Europe contributed.

First King Andrew II of Hungary (1205–1235) considered to employ the Teutonic Knights both to defend the remote province of his kingdom and to stimulate the conversion of the pagan Cumans. For this purpose, he granted the knights the Burzenland (Barcaság, Bârsei) region of Transylvania in 1211. The Cumans only became receptive to the idea of conversion after 1223. Suffering a severe defeat in the battle on the river Kalka by the Mongols in that year, they had to take into consideration the threat of a new Mongol invasion thereafter.

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