Charles de Bourbon was born on 22 September 1523. He died in the castle of Fontenay-le-Comte on 9 May 1590. He was the eighth child of Charles IV de Bourbon, duke of Vendôme. His mother was Françoise d'Alençon.
Charles made a rapid career in the Roman Catholic hierarchy. He was bishop of Nevers (1540-1545), bishop of Saintes (1545-1550, elevated to cardinal in 1548), archbishop of Rouen (1550-1590), bishop of Nantes (1550-1554), Papal legate in Avignon (1565-1590) and bishop of Beauvais (1569-1575). In 1551 he was made Lieutenant-General of Paris and Ile de France. On 31st December 1578 he was made the first commander in the Order of the Holy Spirit.
When the duke of Alençon and Anjou died childless in 1584 while the king was also still childless it was clear that the house of Valois would come to an end with the death of the king and the succession would then pass to the house of Bourbon-Vendôme who were descended from Louis IX. However, the senior member of the family, Henry of Navarre (son of Charles's late elder brother Antoine), was a Protestant. The Catholic League, party to the French Wars of Religion, excluded all Protestants from the succession, which made Charles de Bourbon their champion. In the secret Treaty of Joinville of 31st December 1584 he was anointed by the leaders of the league and a representative of Philip II of Spain. Henry III had Charles imprisoned in the castle of Blois on 23rd December 1588. He was transferred from one castle to another, presumably to prevent escape. On Henry's death in 1589, the League proclaimed Charles king, while still a prisoner and in the castle of Chinon. He was recognized as Charles X by the parliament of Paris on 21st November 1589. His prison was considered too close to Catholic territory, so he was again transferred, this time to Fontenay-le-Comte. The Catholic League issued coins in his name from 2nd August 1589 to his death from 15 Mints, including Paris. Charles, however, renounced the royal title and recognized his nephew Henry IV, whose succession was disputed by the Catholic League.
When the Comte d'Artois ascended the French throne in 1824, he definitively demonstrated Charles de Bourbon's lack of legitimacy by styling himself Charles X of France.