Counts of Celje

The dynasty reached its peak with Ulrich II of Cilli, but with his death in 1456 they also died out, and after a war of succession, the Habsburgs inherited their domains.

He became governor of Carniola and the Windic March in 1332 and was elevated to comital status by Emperor Louis IV in 1341 at Munich, receiving the title Cylie or Cilli derived from Celje Castle.

By acquiring large estates in the adjoining duchies of Styria and Carinthia, in the March of Carniola as well as in the territories of the Hungarian Crown (including Croatia and Slavonia), their influence rose and they became one of the most powerful families in the area.

Count Ulrich I of Cilli, a leader of mercenary soldiers, joined King Louis I of Hungary on his 1354 campaign into Dalmatia and, shortly afterwards, accompanied the Rex Romanorum Charles IV to his coronation at Rome.

Their rapid rise continued after the 1396 Battle of Nicopolis against the Ottoman Empire, where Count Hermann II of Cilli saved the life of King Sigismund of Hungary, the son of the late Emperor Charles IV.

In 1436 he elevated the Counts of Cilli to the rank of Princes of the Holy Roman Empire (although they retained their title of Graf (Slovene: grof)).

After an unsuccessful claim to the Bosnian crown, Cilli obtained some territories in Croatia and Slavonia and in 1452 finally succeeded in forcing Emperor Frederick III to hand over the boy king Ladislaus to his keeping.

With the death of Ulrich II the male line of the Counts of Cilli died out, and after a war of succession all of their estates and property were handed over to the Habsburgs on the basis of the inheritance agreement.