Diet of Augsburg
In the 16th century, twelve of thirty-five imperial diets were held in Augsburg, a result of the close financial relationship between the Augsburg-based banking families such as the Fugger and the reigning Habsburg emperors, particularly Maximilian I and his grandson Charles V. Nevertheless, the meetings of 1518, 1530, 1547/48 and 1555, during the Reformation and the ensuing religious war between the Catholic emperor and the Protestant Schmalkaldic League, are especially noteworthy.
With the Peace of Augsburg, the cuius regio, eius religio principle let each prince decide the religion of his subjects and inhabitants who chose not to conform could leave.
The Elector Frederick persuaded the pope Leo X to have Luther examined at Augsburg, instead of being called to Rome, where the Imperial Diet was held.
Emperor Charles V could not bring himself to openly discuss the matters of religious dispute and cause for division throughout Europe so he often stayed away from the sessions of the Diet.
The committees would prepare material that would be discussed by colleges and once acted upon, the issue entered the plenary session stage, however this was only ceremonial during the Diet of Augsburg.
The Ninety-five Theses, published by Martin Luther in 1517, had sparked the Reformation in the German lands and an increasing number of princes turned Protestant.
After the Great Peasants' Revolt was suppressed, the 1530 Diet was convoked to calm rising tensions over Protestantism, especially due to fears of the Ottoman advance; the forces of Sultan Suleiman the Magnificent had almost taken the Habsburg residence Vienna in 1529 and Emperor Charles V wanted Christianity to unite against the invasions.
According to Joachim Camerarius, his first biographer, he "did not bend the truth to win favor or meet objections; at the same time he avoided unnecessary conflict".
Staying at the Veste Coburg, he made himself present through a variety of publications including the composition of "Admonition to All the Clergy Assembled at Augsburg".
A member of the Saxon group, Justus Jonas, wrote that Luther's work seemed inspired while "rebuking the haughtiness of the higher clergy, forcefully asserting 'the article on necessity', and reducing the opponents to silence".
The tensions between Charles V and the German Lutheran princes were finally resolved with the Peace of Augsburg in 1555, which formally acknowledged Protestantism as a legitimate religion of the Empire.
This attempt to give Catholicism the priority was rejected by many princes, though, and a resolution of the confessional tensions was only achieved at the session in 1555, where the Peace of Augsburg was concluded.
The treaty acknowledged the Augsburg Confession and codified the cuius regio, eius religio principle, which gave each prince the power to decide the religion of his subjects.
