the third war began in 1568, when condé and his ally, gaspard de coligny, suspected that the catholics would try to murder them. they went south and raised an army. a catholic army, led by the king's brother, henry of valois, who would later become henry iii of france, attacked them and won a victory at jarnac. at the battle of jarnac, condé was captured and executed. coligny, now the leader of the main protestant army, fought another battle against the catholics at moncontour. this battle, one of the deadliest of the era, was another protestant defeat. many of the protestants withdrew into the fortress town of saint jean d'angély, and the catholics besieged them there. while the catholics besieged saint jean d'angély and lost thousands of troops, coligny joined forces with the protestant count of montgomery and his army. the protestants marched across france and, in june 1570, defeated the catholics at the battle of arnay-le-duc. the catholics, running out of money, made a peace treaty with the protestants.