Charles de Lorraine, duc de Mayenne (26 March 1554 – 3 October 1611) was a French noble, governor, military commander and rebel during the latter French Wars of Religion. Born in 1554, the second son of François de Lorraine, duke of Guise and Anne d'Este, Mayenne inherited his fathers' position of Grand Chambellan in 1563 upon his death. He fought at the siege of Poitiers for the crown in 1569, and crusaded against the Ottomans in 1572. He served under the command of the king's brother Anjou during the siege of La Rochelle in the fourth war of religion, during which he was wounded. While the siege progressed, his uncle was killed by a cannonball, and he inherited his position as governor of Bourgogne. That same year, his marquisate of Mayenne was elevated to a duché pairie. He travelled with Anjou when he was elected as king of the Commonwealth and was a member of his court there until early 1574 when he departed on crusade again. Returning to France, he served in the fifth war of religion for Anjou, now king Henri III of France, but his badly underfunded army was unable to seriously impede the Protestant mercenary force under Casimir. He aligned himself with the Catholic Ligue that rose up in opposition to the generous Peace of Monsieur and fought in the sixth war of religion that resulted, serving at the sieges of La Charité-sur-Loire and Issoire. During 1576, he married Henriette de Savoie-Villars, securing a sizable inheritance in the south west, and the title of Admiral on the death of her father in 1578. Mayenne was granted full command of a royal army during the seventh war of religion in 1580, besieging the Protestant stronghold of La Mure successfully, and clearing several holdout towns after the peace. In 1582 he was obliged to surrender his title of Admiral to Joyeuse, a favourite of Henri. The following year he was involved in an abortive plan to invade England, though it came to nothing due to lack of funds.
In 1584, the king's brother Alençon died, and the Protestant Navarre became heir to the throne. This was unacceptable to Mayenne, and many other radical Catholics across France. Resultingly, Mayenne, his brother Guise and various family allies formed a second Catholic ligue at Nancy in September 1584, to push the succession of Cardinal Bourbon, Navarre's Catholic uncle. They formed a compact with Philip II of Spain in December, and entered rebellion against the crown in March 1585. Mayenne seized many of the cities of his governate, and the crown was forced to terms in July, conceding to the ligue that Navarre would be excluded from the succession, and that the crown would conduct a war on heresy. Over the following years, Mayenne vigorously pursued attempts to campaign against the Protestants of the south, however Henri's participation was half hearted, and on a frustrated return to Paris in early 1587, Mayenne was at minimum sympathetic to a failed ligueur plan to seize the capital. Returning south he captured Monségur in mid 1587 but was increasingly unable to make progress for lack of funds. In May 1588, Henri engineered a showdown with the radical Catholics of the capital, but was bested and driven from the city. Forced to make concessions he agreed to establish an Edict of Union, with religiousity overriding Salic Law in determining succession, and to appoint Mayenne to lead one of his principal armies for a war against heresy. At the Estates General, demanded by the ligue, that was called a few months later, the Third Estate demanded the funds they offered be given directly to Mayenne. At a breaking point, Henri arranged for the assassination of the duke of Guise and Cardinal Guise in December, upon which his kingdom erupted into broad rebellion.