The Old Swiss Confederacy was a loose alliance of independent communities in what is now Switzerland, formed in the late 13th century. It began with the signing of the Federal Charter of 1291 by the three cantons of Uri, Schwyz, and Unterwalden, which aimed to provide mutual defense against external threats. Over time, more cantons joined, creating a network of alliances that promoted cooperation and military support. By the 15th century, the Old Swiss Confederacy had grown to include 13 cantons, becoming a significant political and military force in Europe. The confederacy was known for its successful battles, such as the Battle of Morgarten in 1315 and the Battle of Sempach in 1386, which solidified its independence from the Holy Roman Empire. The confederacy laid the groundwork for modern Switzerland's federal structure.