Cesare Borgia
Cesare Borgia (1475–1507) was the illegitimate son of Cardinal Rodrigo Borgia, later Pope Alexander VI. Made archbishop of Valencia in 1492 and cardinal in 1493, he resigned in 1498 after his brother's murder and became Duke of Valentinois under Louis XII of France.
Commanding papal armies, he became Duke of Romagna in 1501 and seized Urbino in 1502 before executing his condottieri at Senigallia. His father's death in 1503 exposed him to Pope Julius II; imprisoned in Spain, he escaped to Navarre and was killed at Viana in 1507. His career inspired Machiavelli's The Prince.