 At the death of Henry III of France, the Huguenot Henry of Navarre became by birthright the successor to the French throne (as Henry IV).Although he quickly declared his intention to "maintain and preserve the Catholic, apostolic and roman religion" of the country (), the major French cities sided with the Catholic League and its leader, the Duke of Mayenne (younger brother to the deceased Henry I, Duke of Guise).At that time, the royal army was in a shambles and Henry IV could only count on barely 20,000 men to conquer a rebellious country.