Amadeus of Portugal was a 15th-century Portuguese nobleman who transitioned from a Hieronymite monk to a Franciscan friar. Born João de Menezes da Silva, he became a significant reformer within the Franciscan Order, establishing a distinct branch known as the Amadeiti. He spent much of his religious life in Italy, particularly in Milan, where he served as a confessor to Pope Sixtus IV. He is remembered for his theological writings and his influential prophecies regarding a future era of peace in the church and the world.