About Cesare Borgia:
Cesare Borgia (1475 – 1507), Duke of Valentinois, was an Italian nobleman, politician, and cardinal, whose fight for power was a major inspiration for The Prince by Machiavelli. He was the illegitimate son of Pope Alexander VI (r. 1492–1503) and his long-term mistress Vannozza dei Cattanei. He was the brother of Lucrezia Borgia; Giovanni Borgia (Juan), Duke of Gandia; and Gioffre Borgia (Jofré in Catalan), Prince of Squillace. He was half-brother to Don Pedro Luis de Borja (1460–88) and Girolama de Borja, children of unknown mothers.
After initially entering the church and becoming a cardinal on his father’s election to the Papacy, he became the first person to resign a cardinalcy after the death of his brother in 1498. His father set him up as a prince with territory carved from the Papal States, but after his father’s death he was unable to retain power for long. According to Machiavelli this was due to his planning for all possibilities but his own illness.