Cantons of Switzerland the canton of Schwyz. Six of the 26 cantons are traditionally, but no longer officially, called "half-cantons" (, , , ). In two instances (Basel and Appenzell) this was a consequence of a historic division, whilst in the case of Unterwalden a historic mutual association, resulting in three pairs of half-cantons. The other 20 cantons were — and in some instances still are — though only in a context where it is needed to distinguish them from any half-cantons, typically termed "full" cantons in English. The historic half-cantons, and their pairings, are still recognizable in the first article of the
Territorial evolution of Switzerland Territorial evolution of Switzerland The territorial evolution of Switzerland occurred primarily with the acquisition of territory by the historical cantons of the Old Swiss Confederacy and its close associates. This gradual expansion took place in two phases, the growth from the medieval Founding Cantions to the "Eight Cantons" during 1332–1353, and the expansion to the "Thirteen Cantons" of the Reformation period during 1481–1513. The Helvetic Republic (formed 1798) as revised in the Act of Mediation (1803) added further territories of former Associates of the Swiss Confederacy, notably those of the Abbey of St. Gall and the Three Leagues. The territories