Margaret was the daughter of King Henry II of France and Catherine de' Medici and the sister of kings Francis II, Charles IX and Henry III. Her union with the king of Navarre, which had been intended to contribute to the reconciliation of Roman Catholics and Protestant Huguenots in France, was tarnished six days after the marriage ceremony by the St Bartholomew's Day massacre and the resumption of the French Wars of Religion. In the conflict between Henry III and the Malcontents, she took the side of Francis, Duke of Anjou, her younger brother, and this caused the king to have a deep aversion towards her.