Béla, Duke of Slavonia

Béla (c. 1243 or 1249 –1269) was the youngest and favorite child of King Béla IV of Hungary. His father appointed him Duke of Slavonia in 1260, but he only started to govern his duchy from 1268. He died childless.

Béla was the youngest child and the second son of King Béla IV of Hungary. His mother was Maria Laskarina, daughter of Theodore I Laskaris, Emperor of Nicaea. The year of his birth is uncertain, but he was his parents' youngest child. Taking into account that his sister, Margaret was born in 1242, Mór Wertner, Gyula Kristó and other historians write that Béla was born around 1243. Béla himself stated in a charter of 1269 that "we has not turned twenty-five, we are about twenty", suggesting that he had actually been born around 1249.

King Béla's letter to Pope Innocent IV, which was written in about 1254, contains the first record of Béla's life. The letter refers to a plan of the child Béla's marriage with an unnamed niece of the Pope. However, the marriage never took place.

His father appointed him Duke of Slavonia in 1260. In addition to Slavonia, Béla's duchy included Croatia and Dalmatia. These lands had been governed by Béla's elder brother, Stephen.

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