Duke Amadeus VIII of Savoy, born in 1435, was a significant figure in the history of the House of Savoy. He became the Duke of Savoy in 1439 and is known for his efforts to expand the territory and influence of his duchy. His reign was marked by political maneuvering and alliances, particularly with the Kingdom of France and the Holy Roman Empire. In 1451, Amadeus VIII was elected as the Antipope Felix V, a title he held until 1455. His papacy was controversial, as it occurred during the Western Schism, a period of division in the Catholic Church. After resigning, he returned to his ducal duties and continued to play a role in European politics until his death in 1472.