Bela IV of Hungary

Béla IV
King of Hungary and Croatia
Reign	21 September 1235 – 3 May 1270
Coronation	1214 14 October 1235
Predecessor	Andrew II
Successor	Stephen V
Duke of Styria
Reign	1254–1258
Predecessor	Ottokar V
Successor	Stephen
Born	1206
Died	3 May 1270 (aged 63–64) Rabbits' Island (now Margaret Island, Budapest)
Burial	Minorites' Church, Esztergom
Spouse	Maria Laskarina
Issue more...	Kunigunda Anna Elizabeth Constance Yolanda Stephen V of Hungary Margaret Béla
Dynasty	Árpád dynasty
Father	Andrew II of Hungary
Mother	Gertrude of Merania
Religion	Roman Catholic

Béla IV (1206 – 3 May 1270) was King of Hungary and Croatia between 1235 and 1270, and Duke of Styria from 1254 to 1258. Being the oldest son of King Andrew II, he was crowned upon the initiative of a group of influential noblemen in his father's lifetime in 1214. His father, who strongly opposed Béla's coronation, refused to give him a province to rule until 1220. In this year, Béla was appointed Duke of Slavonia, also with jurisdiction in Croatia and Dalmatia. Around the same time, Béla married Maria, a daughter of Theodore I Laskaris, Emperor of Nicaea. From 1226, he governed Transylvania with the title Duke. He supported Christian missions among the pagan Cumans who dwelled in the plains to the east of his province. Some Cuman chieftains acknowledged his suzerainty and he adopted the title of King of Cumania in 1233. King Andrew died on 21 September 1235 and Béla succeeded him. He attempted to restore royal authority, which had diminished under his father. For this purpose, he revised his predecessors' land grants and reclaimed former royal estates, causing discontent among the noblemen and the prelates.

The Mongols invaded Hungary and annihilated Béla's army in the Battle of Mohi on 11 April 1241. He escaped from the battlefield, but a Mongol detachment chased him from town to town as far as Trogir on the coast of the Adriatic Sea. Although he survived the invasion, the Mongols devastated the country before their unexpected withdrawal in March 1242. Béla introduced radical reforms in order to prepare his kingdom for a second Mongol invasion. He allowed the barons and the prelates to erect stone fortresses and to set up their private armed forces. He promoted the development of fortified towns. During his reign, thousands of colonists arrived from the Holy Roman Empire, Poland and other neighboring regions to settle in the depopulated lands. Béla's efforts to rebuild his devastated country won him the epithet of "second founder of the state" (Hungarian: második honalapító).

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