ON THE LAST day of May 1490, Beatrice wrote to Ercole d’Este thanking him for his condolences. Matthias Corvinus had died unexpectedly in Vienna a month earlier, creating a power vacuum in the kingdom of Hungary and his recently conquered territories in Lower Austria. It also left his widow in a very precarious position. The queen's barrenness did not just prevent her from creating new networks, it made her queenship insecure. If she had given birth to a son, she would have likely become regent after Corvinus's death or played an important role as a dowager queen. Without the king or a son, there was little tying her to power. Beatrice, however, made no mention of the ensuing chaos, instead agreeing with her brother-in-law that Corvinus's death was “damaging to our whole House and to all of our relatives and friends.” Although she had faith that God would ensure her recovery from this loss, she still found herself unable to control her tears and grief. She was, nevertheless, grateful to Ercole's counsel, to which we are not privy, promising to use his advice in difficult times.

Beatrice would have great need of his advice. The queen failed to mention in her letter that the Hungarian Diet had gathered in May to elect Corvinus's successor. There were four contenders for the throne: Władysław II, King of Bohemia, Maximilian I, King of the Romans, János Corvinus, and Władysław's younger brother, Jan I Olbrach, because their father , the King of Poland, wanted each of his sons to have their own realm. Maximilian, son of the Habsburg Emperor Frederick III, claimed that he was entitled to Hungary as a result of a clause in the 1463 Peace Treaty of Wiener Neustadt. Władysław similarly had a hereditary claim to the throne through his mother, a sister of Matthias's predecessor. Both the Habsburg and the Jagiellonian families had bided their time to reclaim their lost territories and campaigned against János to win the favour of Hungary's barons and prelates.

Władysław's relaxed governance of Bohemia made him favourable towards the Hungarians, who hoped the Pole would not interfere in their affairs.