Ulrich II (1406 – 9 November 1456), also known as Ulrich Cillei, was the last Princely Count of Celje

Counts of Celje

The Counts of Cilli or Celje represent the most important medieval aristocratic and ruling house with roots and territory in present-day Slovenia....

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Ulrich II. was the son of Count Frederick II of Celje

Celje

Celje is a typical Central European town and the third largest town in Slovenia. It is a regional center of Lower Styria and the administrative seat of the Urban Municipality of Celje . The town of Celje is located under Upper Celje Castle at the confluence of the Savinja, Ložnica, and Voglajna...

 and his wife Elizabeth, a scion of the Croatian

Kingdom of Croatia (medieval)

The Kingdom of Croatia , also known as the Kingdom of the Croats , was a medieval kingdom covering most of what is today Croatia and Bosnia and Herzegovina in the Balkans.Established in 925, it ruled as a sovereign state for almost two centuries...

 House of Frankopan. Little is known of his youth. In about 1432 he married Catherine, daughter of Đurađ Branković, despot of Serbia

Serbian Despotate

The Serbian Despotate was a Serbian state, the last to be conquered by the Ottoman Empire. Although the Battle of Kosovo in 1389 is generally considered the end of the medieval Serbian state, the Despotate, a successor of the Serbian Empire and Moravian Serbia survived for 70 more years,...

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His influence in the affairs of the Kingdom of Hungary

Kingdom of Hungary

The Kingdom of Hungary comprised present-day Hungary, Slovakia and Croatia , Transylvania , Carpatho Ruthenia , Vojvodina , Burgenland , and other smaller territories surrounding present-day Hungary's borders...

 and the Holy Roman Empire

Holy Roman Empire

The Holy Roman Empire was a realm that existed from 962 to 1806 in Central Europe.It was ruled by the Holy Roman Emperor. Its character changed during the Middle Ages and the Early Modern period, when the power of the emperor gradually weakened in favour of the princes...

 soon overshadowed that of his father, with whom he was raised to a Prince of the Empire

Princes of the Holy Roman Empire

The term Prince of the Holy Roman Empire denoted a secular or ecclesiastical Imperial State, who ruled over an immediate fief directly assigned by the Holy Roman Emperor...

 by Emperor Sigismund of Luxembourg

Sigismund, Holy Roman Emperor

Sigismund of Luxemburg KG was King of Hungary, of Croatia from 1387 to 1437, of Bohemia from 1419, and Holy Roman Emperor for four years from 1433 until 1437, the last Emperor of the House of Luxemburg. He was also King of Italy from 1431, and of Germany from 1411...

 in 1436.