Peace of Augsburg

Concluded at Augsburg on 25 September 1555, this settlement gave Lutheranism a permanent legal place in the Holy Roman Empire alongside Catholicism. Each ruling prince could choose which of the two faiths his territory would follow, an arrangement later summed up in the Latin phrase cuius regio, eius religio, "whose realm, his religion". It ended decades of religious conflict within Germany, but its gaps and ambiguities helped prepare the way for the Thirty Years' War.

The emperor Charles V had hoped to restore a single church in Germany. After defeating the Protestant Schmalkaldic League at the Battle of Mühlberg in 1547, he imposed an interim religious settlement in 1548. Its 26 articles were broadly Catholic, though they allowed priests to marry and the laity to receive both bread and wine. Protestant territories resisted it and drew up their own version at Leipzig.

In 1552 a revolt by Maurice, the Protestant elector of Saxony, and other princes swept the interim away. In the negotiations at Passau that summer even Catholic princes called for a lasting peace, and the agreement reached there gave Lutherans religious freedom, but only until the next imperial diet. That diet was summoned in early 1555. Charles, unwilling to accept the division of Western Christianity as permanent, left the negotiations to his brother Ferdinand.

The settlement rested on three principles. First, the ruler of each territory decided whether it would be Lutheran or Catholic, and his subjects were in general expected to follow. Those who would not conform were allowed to move to a territory of their own faith, selling their property after paying local taxes. Serfs, however, were effectively excluded from it.

Second, the ecclesiastical reservation dealt with the prince-bishops and abbots who ruled territories as churchmen. If one of them became a Protestant, his subjects were not to be converted with him, and he was expected to resign his office, although the agreement did not say so explicitly.

Third, a declaration added by Ferdinand on his own authority protected knights and certain towns where Lutheranism had been practised since the mid-1520s, allowing a few mixed communities to survive. This clause was not made public with the treaty and remained secret for almost twenty years.

The peace recognised only two confessions. Calvinists, except those who accepted a variant version of the Lutheran Augsburg Confession, as well as Zwinglians and Anabaptists, were expressly excluded and remained exposed to charges of heresy. Many dissenters chose to conform outwardly while keeping their beliefs in private. Other Protestant groups won legal recognition only in 1648.

The settlement brought decades of relative calm but did not resolve the deeper disputes. The Cologne War of 1583 to 1588 put the ecclesiastical reservation to the test after the archbishop-elector of Cologne, Gebhard Truchsess von Waldburg, became a Protestant without giving up his see. In 1629, during the Thirty Years' War, the Catholic Edict of Restitution revoked the protections in Ferdinand's declaration. The Peace of Westphalia in 1648 finally replaced the Augsburg system: rulers could no longer force their subjects to convert, territorial religion was fixed by the position in 1624, and Calvinism was recognised.

The religious turmoil also shaped Charles's decision to abdicate and divide the Habsburg inheritance. Ferdinand received the Austrian lands, while Charles's son Philip II took Spain, the Netherlands and the Italian possessions. Historians have sometimes described the Augsburg settlement as a first step towards a Europe of sovereign states.

Our 1530 map shows the patchwork of territories in the Holy Roman Empire before the settlement, and the 1600 map shows the empire in the period of uneasy religious coexistence that followed, across much of today's Germany and Austria.