The Peace of Saint-Germain-en-Laye was a treaty signed on 5 August 1570 at the royal Château of Saint-Germain-en-Laye, ending the third of the French Wars of Religion. It was primarily negotiated by the Protestant queen of Navarre, Jeanne d'Albret.
In the third war, fought between Catholics and Protestants from 1568 to 1570, the Protestant Huguenots had suffered a setback at the Battle of Jarnac (1569), where their general, the prince de Condé, was slain; and following the appointment of Henry of Navarre (later Henri IV) as new leader of the Huguenot cause, the peace treaty was signed by King Charles IX for the Catholics, and by Admiral Gaspard de Coligny for the Huguenots, granting the Huguenots control of four 'fortified towns': La Rochelle, Cognac, Montauban and La Charité for two years.
Moreover, Protestants were henceforth to be allowed to hold public office in France, and Catherine de' Medici, mother of Charles IX, promised to give her daughter Marguerite de Valois in marriage with Henry of Navarre. This peace would be of short duration, as two years later the St. Bartholomew's Day massacre led to the resumption of hostilities.