Cesare Borgia
Cesare Borgia (1475–1507) was the son of Pope Alexander VI. He benefited from Pope Alexander VI's nepotism (placing family in important roles) and became ruler of Romagna, a historical region of Italy, by murdering those who opposed him. He was banished by Pope Julius II and died during the invasion of Castile. His policies were famously described by Niccolò Machiavelli in The Prince.