But how did he die?
According to the most popular historical legend, he was killed with poisoned figs. He had some kind of an illness that made him drowsy and tired all the time; some people claim that was the sign of someone slowly poisoning the king. We know from the chronicles that he ate some figs the day before his death, and he became upset because they tasted funny. Soon after he succumbed to great pains.
Most people blame the Italians. The figs were brought from Ancona. Mátyás had an Italian wife, Beatrice, and they brought him a new Italian doctor short before he died. The chronicle also states that when the king was lying on his deathbed Beatrice was making him drink some "life-giving" potion (I would have been suspicious of that too). It didn't seem to help. It was a popular idea after his death to blame the queen, but not much evidence supported it.
Other historians claim he died of a stroke, or some other natural cause. Some say that eating rotten figs can lead to great stomach pains and eventually to stroke if someone is already predisposed. We'll probably never know for sure. But once again, the death (and life) of King Mátyás is a story most Hungarians are familiar with.
(I remember there was a colorful picture book illustration of his death in one of my elementary school history books. The king was lying in bed, and a lady in a beautiful green Renaissance dress was making him drink from a tiny bottle. There was a plate of figs on the bedside table.)