https://www.hungarianottomanwars.com/1372-1490/the-battle-of-varna-1444-part-three/

After the return of the defeated army in February 1445, the Diet of Rákos Field (near Pest) was at a loss as to whom to give the supreme power to after the death of Ulászló who had no heir. The next king was supposed to be the child of King Habsburg Albert who used to be the only righteous Habsburg king of the Hungarians. However, after his death, Emperor Frederick III (r. 1440-1493) refused to let the late King Albert’s son, László, return from Vienna. In the end, the noble estates appointed seven captain-generals to head the country. The most powerful of these, Hunyadi,  the hero of the anti-Turk struggle, who held the office of Voivode of Transylvania, was then able to advance to the position of governor at the next Diet of Rákos, representing László who was still in Frederick’s captivity.

According to the decision of 5 June 1446, Hunyadi János was allowed to exercise supreme power as governor under the supervision of a council of state and with a number of other restrictions. The voivode-chief captain, who directly ruled Trans-Tisza River Region and Transylvania, was in possession of the royal castles, the king’s armies, and the mints. Hunyadi was obliged to seek the approval of the Diet for appointments and donations – they could also pass laws together – and his expenditures were supervised by the Treasurer. Initially, Hunyadi did not manage the royal estates and the income from them, but in 1447, together with Buda Castle, he finally acquired this right. At this Diet, he also succeeded in abolishing the post of captain-general, thus further increasing the power of himself and his party, which was largely composed of commoners.

At the beginning of his seven-year reign, Hunyadi waged war against Frederick III, who held the heir to the throne, but after fruitless fighting against the Habsburgs’ Hereditary Provinces, he concluded a truce for two years. He also organized a campaign against the Bohemian Hussites, who had been rebelling in the Highlands (northern part of Hungary), but proved unable to defeat the Czech mercenary leader Jiskra throughout his life (only Matthias could force him to make peace by taking him into his mercenary army).

As governor, Hunyadi János continued his struggles in the Balkans with the help of the kingdom’s revenues: after 1445 he forced the “buffer states” south of the Kingdom of Hungary to pay homage to Hungary, and in 1448 he attacked the Ottoman Empire, he was the head of a Christian – Hungarian-Hungarian-Albanian – coalition. Defeated in the second battle of Kosovo (Rigómező), against more than twice his superior numbers, Hunyadi later retreated to defend the frontiers. To add to his troubles, on his return home, the Serbian despot George Brankovic took revenge for his capture by the Serbian governor and imprisoned him in the castle of Szendrő, from where he was released only after paying a heavy ransom. Read more about the Battle of Kosovo in 1448 on my page:

https://www.hungarianottomanwars.com/1372-1490/battle-of-kosovo-polje-1448/

In 1450, Hunyadi and Frederick sat down again in Pozsony (Pressburg, Bratislava) to discuss the fate of László, but the emperor again refused to return the heir to the throne, and Ulrik Cillei accused him of trying to seize the supreme power for himself. After long negotiations, Albert’s son returned home in 1452 – without the Holy Crown – and Hunyadi abdicated a year later, in 1453, in favor of the king, who had just turned 14.

King László V (r. 1453-1457) then bestowed on him the titles of Captain-General and Count of Beszterce, but he no longer claimed his services as governor. After that, the young king was manipulated by the circle of László’s supporters in Vienna and by Frederick III, who shaped Hungarian domestic politics. There was an alliance between the high lords, namely between Cillei, Újlaki Miklós, and  Palatine Garai Miklós who moved the young king as a puppet. Hunyadi retreated to Transylvania and devoted himself to organizing the defense against the Turks, increasing his glory with a number of deeds, including the triumph of Nándorfehérvár (Belgrade), until his death in 1456.

During his reign, Hunyadi János was suspected by many of using his power to usurp the throne – it is not known to what extent these accusations are true, but for reasons beyond his control, this was achieved after his death with the reign of Matthias Corvinus, his son.

The governors of the Kingdom of Hungary were:

/Source: partly from Rubicon/