The "Army of the Andes" was a military force led by José de San Martín during the early 19th century. It played a crucial role in the South American wars of independence, particularly in the liberation of Argentina, Chile, and Peru from Spanish colonial rule. The army was formed in 1817 and consisted of troops from various regions, including Argentina and Chile. The campaign began with a daring crossing of the Andes Mountains, which was a significant logistical challenge. The successful maneuver allowed the army to surprise Spanish forces in Chile and later advance into Peru, contributing to the eventual independence of several South American nations.