First war of Kappel

The First War of Kappel (Erster Kappelerkrieg) was an armed conflict in 1529 between the Protestant and the Catholic cantons of the Old Swiss Confederacy during the Reformation in Switzerland. It ended, without any battle having been fought, with the first peace of Kappel (Erster Landfriede).

Under the lead of Huldrych Zwingli, the Protestant canton and city of Zürich had concluded with other Protestant cantons a defence alliance, the Christliches Burgrecht, which also included the cities of Konstanz and Strasbourg. The Catholic cantons in response had formed an alliance with Ferdinand of Austria.

Conflicts between the two sides arose also over the situation in the common territories, especially the Thurgau, where the administration changed bi-annually between cantons and which thus switched between Catholic and Protestant rules. Several mediation attempts failed, such as the disputation of Baden in 1526.

After numerous minor incidents and provocations from both sides, a Catholic priest was executed in the Thurgau in May 1528, and the Protestant pastor J. Keyser was burned at the stake in Schwyz in 1529. The last straw was the installation of a Catholic vogt at Baden. Zürich declared war on 8 June, occupied the Thurgau and the territories of the Abbey of St. Gall and marched to Kappel at the border to Zug.

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