What was the significance of the Peace of Augsburg in 1555?

The significance of the Peace of Augsburg in 1555 lies largely in its establishment of the principle of "cuius regio, eius religio," which translates to "whose realm, his religion." This accord allowed the rulers of the various German states within the Holy Roman Empire to choose either Lutheranism or Catholicism as the official faith of their territories. This decision meant that subjects were expected to practice the religion of their ruler, or alternatively, to migrate to a region where their preferred faith was practiced.

This ruling was a critical moment in the religious conflict of the Reformation, as it acknowledged the legitimacy of Protestantism in the Empire, which had previously been regarded as heretical by Catholic authorities. It provided a temporary peace between the Catholic and Protestant factions and was significant in shaping the religious landscape of Europe. By recognizing the authority of rulers to dictate religious practice, the Peace of Augsburg also set a precedent for the later concept of state sovereignty in matters of religion, influencing the development of nation-states.