Charles IX was a monarch of the House of Valois who ruled as King of France from 1560 until his death. He ascended the throne of France upon the death of his brother Francis II.
After decades of tension, war broke out between Protestants and Catholics after the massacre of Vassy in 1562. In 1572, after several unsuccessful peace attempts, Charles ordered the marriage of his sister Margaret of Valois to Henry of Navarre, a major Protestant leader and the future King Henry IV of France, in a last desperate bid to reconcile his people.
Facing popular hostility against this policy of appeasement, Charles allowed the massacre of all Huguenot leaders who gathered in Paris for the royal wedding at the instigation of his mother Catherine de' Medici. This event, known as the St. Bartholomew's Day Massacre, crippled the Huguenot movement.
Charles sought to take advantage of the disarray of the Huguenots by ordering the Siege of La Rochelle, but was unable to take the Protestant stronghold.
He died without legimate issue in 1574 and was succeeded by his brother Henry III.