Catherine de' Medici and St. Bartholomew's Day Massacre
It is impossible to imagine that Catherine de' Medici did not plan the St. Bartholomew's Day massacre (23-24 August 1572). The immediate reason was personal, she hatred Coligny, who dominated Charles IX. The failed attempt against Coligny's life on 22 August (attributed to her), might have induced a state of panic, as a Huguenot uprising was to be expected.
The guilt of the massacre rests upon Catherine de' Medici, she was a ruler whose political decisions were governed by her personal feelings. Probably the failure to kill the admiral was the immediate cause of the massacre of St. Bartholomew's Day. If Coligny had been killed, the massacre probably would not have happened.
King Charles IX died on May 30, 1574. As one of his last commands required, the Queen Mother assumed the regency. The Politiques, the compromise party, whose aim was to establish religious tolerance, raised against Catherine for assuming the regency without consent of the estates. They and the political Huguenots now demanded political reforms, and intended to reach an agreement with Catherine before the arrival of the new King, Henry III, from Poland.
But Catherine refused to deal with any matter of state until the arrival of her son. Once installed, instead of considering the demands they made, Henry III expressed his determination to wage war against the Huguenots and the Politiques, whose union became very strong, especially in the south.
One of the results of the massacre of St. Bartholomew was the crystallization of the liberal Catholic element represented by the marshal Montmorency and his brother, Damville, into a real political party. It was composed of a group of ambitious young nobles, more interested in politics than religion, hostile both to the Queen Mother and to the Guises. The youngest son of Catherine de' Medici, the Duke of Alençon, entered the political scene by joining them, thus threatening Henry's throne.
The Peace of Monsieur
In this crisis, Catherine de' Medici did not hesitate to send armed detachments from Rouen, Orléans, and Chartres to surround Alençon. But Henry of Navarre, the Prince of Condé, the Duke of Alençon, and Damville had the winning cards. The King had no choice but to accept to make peace.
While Paris was already preparing for siege, Henry III signed the Edict of Beaulieu on May 6, 1576. The peace, called the Peace of Monsieur, due to the Duke of Alençon strong involvement, was the most complete charter yet given to the Huguenots, as it implied both toleration of the religion and political reform. The Duke of Alençon now detained a position stronger than that of Henry of Navarre.