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 Cantons to the "Eight Cantons" during 1332–1353, and the expansion to the "Thirteen Cantons" of the Reformation period during 1481–1513.
Source: Wikipedia — Territorial evolution of Switzerland (CC BY-SA 4.0)