John Corvinus (Hungarian: Corvin János, Croatian: Ivaniš Korvin; 2 April 1473 – 12 October 1504) King of Bosnia (1495–1499). He was the illegitimate son of Matthias Corvinus, King of Hungary, and Barbara, supposed to be the daughter of a burgess of Breslau while there have been claims that he was actually the son of Beatrice of Naples, his father's second wife who was 16 years old at the time.