Henry's early career is largely unknown. According to historian Jenő Szűcs, he belonged to Béla IV's accompaniment, who fled Hungary through Transdanubia, escaping from the invading Mongols after the disastrous Battle of Mohi in 1241. It is possible that the young Henry, whose inherited lands laid in the escape route along the Austrian border, entered court service there and remained a member of the escort in Dalmatia, where Béla and his family took refugee in the well-fortified towns on the coast of the Adriatic Sea. Without any doubt as to his identity, Henry first appears in contemporary documents in 1244, when he was made "ispán" of Vas County. He held the position at least until December 1245 (but it is plausible he served in this capacity until 1247). Thereafter, he functioned as "ispán" of Somogy County from 1247 to 1260. Meanwhile, Henry became one of the most powerful barons of the realm, when he was appointed Judge royal in 1254, the second most prestigious office in the royal court. He held the dignity until June/November 1260. His deputy was vice-judge royal Nicholas Tengerdi at least from 1256. Henry participated in the royal campaign in the summer of 1260, when Béla and his allies invaded Moravia, but Ottokar II vanquished them in the Battle of Kressenbrunn on 12 July 1260. The defeat forced Béla to renounce Styria in favor of the King of Bohemia in the Peace of Vienna, which was signed on 31 March 1261.