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In contrast to the role Charles had forced upon Frederick in the 1547-1548 Diet of Augsburg, the Palatinate diplomatic position at the important imperial Diet of Augsburg in 1555 favored the Protestant cause. This meeting produced the important “Religious Peace of Augsburg” which recognized both Lutheranism, in the form of the Augsburg Confession, and Catholicism as legal confessions in the Holy Roman Empire; Reformed Protestantism was excluded. All secular princes were granted the jus reformandi— the right to determine the religion of their territories. This principle is summed up in the Latin dictum cuius regio, eius religio (“ whose region, his religion”).

...Ordinary citizens were also denied the right to determine their faith but were allowed to emigrate if their theological convictions differed with the sovereign’s religious policy.