Catherine de' Medici

Born in Florence in 1519 to the Medici family, Catherine married the French king's second son at fourteen in a match arranged by her cousin, Pope Clement VII. Her husband Henry II kept her from power for years, favoring his mistress Diane de Poitiers, until his accidental death in 1559 forced Catherine into the political arena as mother to the frail fifteen-year-old Francis II. When Francis died the next year, she became regent for ten-year-old Charles IX and gained sweeping powers she would wield through the reigns of all three sons. She faced constant religious war between Catholics and Huguenots, a powerful Guise faction scheming to install its own dynasty, and a throne losing prestige with each crisis. At first she compromised with the Huguenots, then turned to hardline persecution - including the St. Bartholomew's Day massacre of 1572 that killed thousands and stained her legacy. Her letters show ruthlessness; her results show desperation. Without her, the House of Valois likely falls.