The Cardinal of Lorraine, who had supervision of the clergy, and Henry, Duke of Guise, the uncle of the king, who directed the military affairs, were both uncompromising in their hostility to the Protestants. Antony of Bourbon, King of Navarre, and his brother Louis, Prince of Condé, being excluded from the governmental administration, united with the Calvinists for the overthrow of the regime, under pretext of religious zeal. Catherine de Medici, mother of the king, and niece of Pope Clement VII., jealous of a power in which she could not participate, favored the designs of Louis, and employed her art in stimulating the opposition of the reformers to the administration of the Duke of Guise. Under these circumstances a conspiracy against the duke was formed at Amboise, which led to a murderous onslaught, and inaugurated civil war. Louis was captured and condemned to death.
In the midst of the distraction of conflicting parties Francis I. died, and Charles IX., in 1560, succeeded to the throne at the age of ten years. Catherine de Medici, his mother, with the acquiesence of parliament, administered the affairs of government. Although a bigoted Catholic, yet having no principle but the love of sway, she was ready to support any faction or creed that administered to her power, or removed an obstacle to her ambition. Without profound views of policy, she was incapable of either originating a great national object, or of supporting it by adequate measures. So indomitable was her passion for dominion, that it as much obdurated her maternal feelings as it disqualified her for a judicious regent. She even studied to incapacitate her sons for the exercise of the governmental functions, and to divert their attention from the state of national affairs. With this end in view she involved them in the grossest dissipation, and strove to keep them in a perpetual whirl of voluptuous intoxication. Perfect in the art of dissimulation, she cajoled Catholics and Protestants. Anxious to obtain the support of all parties, she alternately favored the one and the other. To embarrass the Duke of Guise she threw everything into confusion; but to conciliate the Protestants she had to redeem her pledges; and in spite of the opposition of the court, to issue an act of toleration in their favor.