Temporarily freed from war with France by the 1529 Treaty of Cambrai and the denouncement of the ban on Luther by the Protestant princes at Speyer that year, the Emperor revisited the issue next at the Diet of Augsburg in 1530, by which time it was well-established. With the Ottoman threat growing (see below), he needed to ensure that he was not facing a major schism within Christianity. He refuted the Lutheran position (Augsburg Confession) (Confessio Augustana) with the Confutatio Augustana, and had Ferdinand elected King of the Romans on 5 January 1531, ensuring his succession as a Catholic monarch. In response, the Protestant princes and estates formed the Schmalkaldic League in February 1531 with French backing. Further Turkish advances in 1532 (which required him to seek Protestant aid) and other wars kept the emperor from taking further action on this front until 1547 when imperial troops defeated the League at the Battle of Mühlberg, allowing him to once more impose Catholicism. In 1541 Ferdinand's appeal to the estates general for aid against the Turks was met by demand for religious tolerance. The triumph of 1547 turned out to be short lived with French and Protestant forces again challenging the emperor in 1552 culminating in the Peace of Augsburg in 1555. Exhausted, Charles started to withdraw from politics and hand over the reins. Protestantism had proved too firmly entrenched to enable it to be uprooted. Austria and the other Habsburg hereditary provinces (and Hungary and Bohemia, as well) were much affected by the Reformation, but with the exception of Tyrol the Austrian lands shut out Protestantism. Although the Habsburg rulers themselves remained Catholic, the non-Austrian provinces largely converted to Lutheranism, which Ferdinand I largely tolerated. Counter-Reformation (1545–1563) The Catholic response to the Protestant Reformation was a conservative one, but one that did address the issues raised by Luther. In 1545 the long running Council of Trent began its work of reform and a Counter-Reformation on the borders of the Habsburg domains. The Council continued intermittently until 1563. Ferdinand and the Austrian Habsburgs were far more tolerant than their Spanish brethren, and the process initiated at Trent. However his attempts at reconciliation at the Council in 1562 was rejected, and although a Catholic counteroffensive existed in the Habsburg lands from the 1550s it was based on persuasion, a process in which the Jesuits and Peter Canisius took the lead. Ferdinand deeply