Stephen IV was King of Hungary and Croatia, ascending to the throne between 1163 and 1165, when he usurped the crown of his nephew, Stephen III. He was the third son of Béla II of Hungary, and when his conspiracy against his brother Géza II failed, he was exiled from Hungary in the summer of 1157. He first sought refuge in the Holy Roman Empire, but received no support from Emperor Frederick I. Shortly afterwards he moved to the Byzantine Empire, where he married a niece of Emperor Manuel I Komnenos, Maria Komnene, and converted to the Eastern Orthodox Church.

Stephen III was King of Hungary and Croatia between 1162 and 1172. He was crowned king in early June 1162, shortly after the death of his father, Géza II. However, his two uncles, Ladislaus and Stephen, who had joined the court of the Byzantine Empire, challenged his right to the crown. Only six weeks after his coronation, the Byzantine Emperor Manuel I Komnenos launched an expedition against Hungary, forcing the Hungarian lords to accept Ladislaus' rule. Stephen sought refuge in Austria, but returned and seized Pressburg. Ladislaus, who died on 14 January 1163, was succeeded by Stephen's younger uncle and namesake, Stephen IV, without resistance, but his rule was unpopular. The young Stephen defeated his uncle on 19 June 1163 and expelled him from Hungary.