November 9, 1456 – Ulrik II, the last of the Celje dynasty, is murdered in Belgrade.
"The Last of Celje", Frideric's son, was destined from childhood to continue the rise of the Celje dynasty in his father's place.
Ulrik was married to Catherine, daughter of the Serbian despot Jurij Branković, from 1433, and the numerous love affairs, which are also mentioned by chroniclers, did not affect his career aspirations. The high positions of his relatives provided him with extremely high political starting points - various viceroyalties and other political and administrative tasks in Bohemia and Hungary, among which he had the greatest hopes from the guardianship of the minor Hungarian king Ladislaus the Posthumous (son of Albrecht II), who was crowned by his mother a few months after his birth in 1440. Of course, he diligently turned the guardianship functions to his advantage, and in doing so he also had powerful rivals and opponents - especially the Habsburgs and part of the Hungarian nobility.
In the race for prestige, he concluded a truce with the Habsburgs in 1443 with a famous bilateral inheritance treaty, according to which the estates within the Holy Roman Empire would be inherited one after the other if they remained without male descendants. Some historians interpret this agreement with the Habsburgs as an agreement that the Celje people would withdraw from high politics in the empire and focus on the Balkans in exchange for recognition of princely status. They even mention the "Yugoslav policy" of the Celje princes.
In any case, due to his guardianship of the young Hungarian king Ladislaus and his status as "Hungarian governor", Ulrik gained ardent opponents among the local Hungarian nobility, so much so that he was beheaded in Belgrade on November 9, 1456. The fatal blow with a sword was allegedly inflicted on him by Ladislaus (Laszlo) Hunyadi, the son of Ivan Hunyadi, the influential leader of the Hungarian anti-Celtic movement, who had previously fallen on a crusade in front of Belgrade.
Ulrik had three children, but they died before him (Jurij in 1443, Herman in 1452, and Elisabeth in 1455).
Source: http://www.celjskozasavski.si/osebe/celjski-ulrik-ii./223/
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