Swiss Reformation

The Protestant Reformation in Switzerland was promoted initially by Huldrych Zwingli, who gained the support of the magistrate (Mark Reust) and population of Zürich in the 1520s. It led to significant changes in civil life and state matters in Zürich and spread to several other cantons of the Old Swiss Confederacy. Seven cantons remained Roman Catholic, though, which led to inter-cantonal wars known as the Wars of Kappel. After the victory of the Catholic cantons in 1531, they proceeded to institute counter-reformatory policies in some regions. The schism and distrust between Catholic and Protestant cantons would define their interior politics and paralyse any common foreign policy until well into the 18th century.

Despite their religious differences, and despite an exclusively Catholic defence alliance of the seven Catholic cantons (Goldener Bund), further major armed conflicts directly between the cantons did not occur. Soldiers from both sides fought in the French Wars of Religion.

In the Thirty Years' War, the thirteen cantons managed to maintain their neutrality, partly because all major powers in Europe depended on Swiss mercenaries, and would not let Switzerland fall into the hands of one of their rivals. The Three Leagues (Drei Bünde) of the Grisons, at that time not yet a member of the confederacy, were involved in the war from 1620 on, which led to their loss of the Valtellina from 1623 to 1639.

After the violent conflicts of the late 15th century the Swiss cantons had had a generation of relative political stability. As part of their struggle for independence, they had already in the 15th century sought to limit the influence of the Church on their political sovereignty. Many monasteries had already come under secular supervision, and the administration of schools was in the hands of the cantons, although the teachers generally still were priests.

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