The rise of federalism in Switzerland began on 12 September 1848, with the creation of a federal constitution in response to a 27-day civil war, the Sonderbundskrieg.
The 1848 constitution represented the first time, other than when the short-lived Helvetic Republic had been imposed, that the Swiss had a central government instead of being simply a collection of autonomous cantons bound by treaties.
Sonderbund War
thumb|left|The federal troops during the Sonderbund war
In 1847, the period of Swiss history known as Restoration ended with 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; in the 19th century the Protestant population 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. The invasion caused a revolt, mostly because rural cantons were strongholds of ultramontanism.
The Sonderbund was in violation of the Federal Treaty of 1815, §6, which forbade separate alliances, and the Radical majority in the Tagsatzung dissolved it on 21 October 1847. A confederate army was raised against the members of the Sonderbund, composed of soldiers of all the other states except Neuchâtel and Appenzell Innerrhoden, which stayed neutral. Ticino, while a Catholic canton, did not join the Sonderbund and fought alongside the Protestants.
The war lasted for less than a month, causing fewer than 100 casualties. Apart from small riots, this was the last armed conflict on Swiss territory.
At the end of the Sonderbund War, the Diet debated a new federal constitution drawn up by Johann Conrad Kern (1808–1888) of Thurgau and Henri Druey (1790–1855) of Vaud. In the summer of 1848 this constitution was accepted by fifteen and a half cantons, with Uri, Schwyz, Unterwalden, Valais, Ticino and Appenzell Innerrhoden opposing. The new constitution was declared on 12 September 1848.
Federal Constitution
1848 Constitution
thumb|The Federal Constitution of 1848
The new constitution created, for the first time, Swiss citizenship in addition to cantonal citizenship. A federal central government was set up to which the cantons gave up certain parts of their sovereign rights. The Federal Assembly was made up of two houses: Council of States (Ständerat), composed of two deputies from each canton (44 members at the time) and the National Council (Nationalrat) made up of deputies elected three years, in the proportion of one for every 20,000 citizens or fraction over 10,000 from each canton. Each member of the Federal Council heads one of seven executive departments. The chairman of the council also holds the title of President of the Swiss Confederation for a one-year term, with the position rotating among the members of the Federal Council.
The judiciary (Bundesgericht) was made up of eleven members elected for three years by the Federal Assembly. The Bundesgericht was chiefly confined to civil cases in which the Confederation was a party, but also took in great political crimes.