Béla IV (1206–1270), King of Hungary (1235–70) and of Croatia (1235–70), duke of Styria 1254–58.

One of the most famous kings of Hungary, he distinguishes himself through his policy of strengthening of the royal power following the example of his grandfather Bela III, and by the rebuilding of Hungary after the catastrophe of the Mongolian invasion in 1241.

For this reason he is called by the Hungarians "the second founder of our country".