Amadeus VIII, Duke of Savoy

Amadeus inherited the county at eight in 1391 and spent twenty-five years building a state that worked: diplomatic deals, internal reforms, institutions that outlasted him. Emperor Sigismund elevated Savoy to a duchy in 1416, making Amadeus its first duke. He abdicated in 1440 and withdrew to a semi-monastic life. Then the Council of Basel elected him pope in 1439 as Felix V, opposing Eugene IV in a schism that dragged into Nicholas V's reign. He was the last antipope to command real clerical support, though he resigned in 1449, two years before his death.