England, who bore a greater grudge against France than he held against the Emperor for standing in the way of his divorce, joined Charles in his invasion of France. Although the Spanish army was soundly defeated at the Battle of Ceresole, in Savoy Henry fared better, and France was forced to accept terms. The Austrians, led by Charles's younger brother Ferdinand, continued to fight the Ottomans in the east. With France defeated, Charles went to take care of an older problem: the Schmalkaldic League. Perhaps more important to the strategy of the Spanish king, the League had allied itself with the French, and efforts in Germany to undermine the League had been rebuffed. Francis's defeat in 1544 led to the annulment of the alliance with the Protestants, and Charles took advantage of the opportunity. He first tried the path of negotiation at the Council of Trent in 1545, but the Protestant leadership, feeling betrayed by the stance taken by the Catholics at the council, went to war, led by the Saxon elector Maurice. In response, Charles invaded Germany at the head of a mixed Dutch-Spanish army, hoping to restore the Imperial authority. The Emperor personally inflicted a decisive defeat on the Protestants at the historic Battle of Mühlberg in 1547. In 1555, Charles signed the Peace of Augsburg with the Protestant states and restored stability in Germany on his principle of cuius regio, eius religio ("whose realm, his religion"). Charles's involvement in Germany would establish a role for Spain as protector of the Catholic Habsburg cause in the Holy Roman Empire. In 1526, Charles married Infanta Isabella, the sister of John III of Portugal. In 1556 he abdicated from his positions, giving his Spanish empire to his only surviving son, Philip II of Spain, and the Holy Roman Empire to his brother, Ferdinand. Charles retired to the monastery of Yuste (Extremadura, Spain), and died in 1558. Philip II (1558–1598) Spain was not yet at peace, as the aggressive Henry II of France came to the throne in 1547 and renewed the conflict with Spain. Charles' successor, Philip II, aggressively conducted the war against France, crushing a French army at the Battle of St. Quentin in Picardy in 1557 and defeating Henry again at the Battle of Gravelines the following year. The Peace of Cateau-Cambrésis, signed in 1559, permanently recognized Spanish claims in Italy. In the celebrations that followed the treaty,