The Catholic League of France, sometimes referred to by contemporary Catholics as the Holy League, was a major participant in the French Wars of Religion. The League, founded and led by Henry I, Duke of Guise, intended the eradication of Protestantism from Catholic France, as well as the replacement of the French King Henry III, who had acquiesced to Protestant worship in the Edict of Beaulieu (1576). The League also fought against Henry of Navarre, the Protestant prince who became presumptive heir to the French throne in 1584.

Henry I, Prince of Joinville, Duke of Guise, Count of Eu, sometimes called Le Balafré ('Scarface'), was the eldest son of Francis, Duke of Guise, and Anna d'Este. His maternal grandparents were Ercole II d'Este, Duke of Ferrara, and Renée of France. Through his maternal grandfather, he was a descendant of Lucrezia Borgia and Pope Alexander VI.