Matthias Corvinus (Civ6)/Civilopedia

Matthias Corvinus harnessed his ambition and thirst for glory in the cause of regenerating the Hungarian crown and kingdom. A true prince of the nascent Renaissance, he was both a patron of humanists and a mighty battlefield commander. At the time of his death, the Kingdom of Hungary was the largest of Europe's kingdoms, but these gains could not be maintained and collapse followed his short and glorious life.
Born in Kolozsvár (Cluj in modern Romania) as the second son of the Hungarian nobleman and commander Janos Hunyadi, Matthias inherited the family's holdings upon the death of his father and older brother, who were executed for their involvement in the assassination of an ally of Hungary's then-reigning king, Ladislaus V. But when Ladislaus himself died without heir in 1457, the Diet of Hungary elected the young Matthias to be king, marking the first time a noble had been promoted to the throne. Some nobles of Hungary and the rulers of Europe celebrated this election in the time-honored fashion for contested succession—they launched revolts and wars.
Despite being only fourteen years old, and nominally under the control of a regent, Matthias nonetheless executed his reign under his own terms. One of his first acts, for instance, was to secure a peace between a group of Romanians and Vlad Dracula, Prince of Wallachia (yes, that Vlad Dracula). He was able to successfully wrestle the crown of Hungary away from Emperor Frederick III, and by extending his royal prerogative was able to levy an extraordinary tax to pay for one of the first standing professional national armies in Europe—the famous Black Army. He attempted an extensive reform of the laws and customs of Hungary in order to consolidate administrative rule of his kingdom.
Matthias was often at war. His enemies included the Ottoman Empire and the Holy Roman Empire (he successfully laid siege to Vienna at one point), as well as nobles of Saxony, Moldavia, Bohemia, and Poland. Hungary's position at the nexus of Eastern Europe and on the margins of the Ottoman Empire meant that the shifting dynastic politics of the region, webs of specific prerogatives and customary rights, and ambitious nobility often led to uprisings within his own lands. These he suppressed, brutally.
In addition to being a successful battlefield general, he was also notable for his love of learning. Under his direction, his library in Buda, the Bibliotheca Corviniana, became one of the world's greatest libraries in terms of scope and quality, said to be second only to the Vatican Library. He encouraged and patronized humanists, and his third wife, Beatrice of Naples, is credited with bringing the Renaissance's attitudes to Hungary, marking the first place the Renaissance spread outside of the borders of Italy.
An ardent Catholic, he saw the defense of the faith in both physical and spiritual terms. While this usually took the form of direct conflict with the Ottoman Sultans and the proto-Protestant Hussites of Bohemia, he was not averse to acting against the temporal authority of the church, including dispensing church property on his own authority and supporting factions opposed to the Papal states.
Matthias was married three times, but died without a legitimate heir. His preference was that he be succeeded by his illegitimate son, Janos Corvinus, but Matthias fell sick and died, leaving Hungary open to a new succession crisis, from which Vladislav II, King of Bohemia emerged to rule Hungary.
The impact of his reign is complex. His rapacious taxation of the Hungarian people funded a series of wars designed to extend the limits of his crown lands. Matthias was a canny political player in the region and a true patron of the letters, a lover of learning at a time when that was not yet seen as a virtue of princes. His personal courage and cunning is beyond dispute (once he escaped capture and evaded his pursuers by pretending to be a local groom). He left behind a Hungary whose territory was larger than the one whose throne he ascended, but these gains could not stand. The ruler who tortured and executed suspected rebels is also the man who wrote a code of laws calling for the constraint of the king by laws and institutions to serve as a check on arbitrary authority.
Matthias Corvinus is still remembered fondly in Hungarian folk tales, where he is depicted travelling the countryside in disguise, dispensing justice on behalf of the poor and downtrodden.