Switzerland as a federal state

The rise of Switzerland as a federal state began on 12 September 1848, with the creation of a federal constitution, which was created in response to a 27-day civil war in Switzerland, the Sonderbundskrieg. The constitution, which was heavily influenced by the United States Constitution and the ideas of the French Revolution, was modified several times during the following decades and wholly replaced in 1999. The constitution represents the first time that the Swiss were governed by a strong central government instead of being simply a collection of independent cantons bound by treaties.

In 1847, the period of Swiss history known as Restoration ended with the breaking out of a war between the conservative Roman Catholic and the liberal Protestant cantons (the Sonderbundskrieg). The conflict between the Catholic and Protestant cantons had existed since the Reformation, and in the 19th century the Protestant population now had a majority. The Sonderbund (German: separate alliance) was concluded after the Radical Party had taken power in Switzerland and had, thanks to the Protestant majority of cantons, taken measures against the Catholic Church such as the closure of monasteries and convents in Aargau in 1841. When Lucerne, in retaliation, recalled the Jesuits the same year, groups of armed radicals ("Freischärler") invaded the canton. This caused a revolt, mostly because rural cantons were strongholds of ultramontanism.

The Sonderbund was in violation of the Federal Treaty of 1815, §6, which expressly forbade such separate alliances, and the Radical majority in the Tagsatzung decided to dissolve the Sonderbund on 21 October 1847. The confederate army was raised against the members of the Sonderbund. The army was composed of soldiers of all the other states except Neuchâtel and Appenzell Innerrhoden which had stayed neutral. Ticino, while a Catholic canton, did not join the Sonderbund and fought with the Protestants.

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