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.

Conflicts between the two religions arose also over the situation in their territories, especially the Thurgau, where the administration changed biannually between cantons and so switched between Catholic and Protestant rules.

Numerous minor incidents and provocations occurred on both sides, such as a Catholic priest being executed in the Thurgau in May 1528 and the Protestant pastor J. Keyser being burned at the stake in Schwyz in 1529.

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 of Zug.

[1] The peace agreement (Erster Landfriede) was not favourable for the Catholics, who had to dissolve their alliance with the Austrian Habsburgs.