[2] However, the Federal Project of 1655 was rejected by the cantons of Central Switzerland, who viewed it as a threat to their dominance established by the 1531 Second Landfrieden, as a result of the Second War of Kappel.

[2] In September 1655, tensions escalated when Protestants living in Arth, a village in the Catholic canton of Schwyz, fled to Zürich and were granted asylum.

[2] The Antistes of Zürich, Johann Jakob Ulrich, declared that Swiss Protestants had a sacred duty to take up arms against the "religious tyrants" of Schwyz.

On an extraordinary Federal Diet in December, Zürich demanded that those responsible be punished, that formal apologies be made and the dissolution of the Golden League.

On 7 January, Hans Rudolf Werdmüller led the Zürcher main army to the strategic city of Rapperswil and placed it under siege.

[2] All troops from Lucerne and Zug that were not already summoned to guard the borders, gathered in Muri and united at Boswil with battalions from the Freie Ämter.

[citation needed] Peace negotiations were mediated by the cantons of Fribourg, Solothurn, Basel, and Schaffhausen, as well as by foreign diplomats, most notably the French ambassador Jean de La Barde.

[2] In the resulting Third Landfrieden on 7 March, both parties agreed to cease hostilities, grant amnesty for misconduct committed during the war and to return to the status quo ante bellum.

Controversial issues such as damage compensations were transferred to an arbitral tribunal,[2] but bad blood within the commission caused many cases to remain unresolved.