Army of the Andes

The Army of the Andes (Spanish: Ejército de los Andes) was a military force created by the United Provinces of the Río de la Plata (Argentina) and mustered by general José de San Martín in his campaign to free Chile from the Spanish Empire. In 1817, it crossed the Andes Mountains from the Argentine province of Cuyo (his staging point being the current-day province of Mendoza, Argentina), and succeeded in its objective by dislodging the Spanish from the country.

The exact number of the army varies between different sources; some have put the number as low as 3500, while others have it being as high as 6000 men. The army consisted of Argentines and Chileans, and included some 1200 auxiliaries to help in provisioning and supply, as well as a complement of artillery. The Congress of Tucumán endorsed San Martín's proposal to form an army to fight the royalists in Chile, and between August 1814 and February 1817, San Martín trained his troops to prepare them for their ordeal. While the army was made up of a less than experienced military force, San Martín intended to lead, with regular discipline and equipment, a proper army and not a "motley crew" into battle.

For the crossing of the mountains, the Army was divided into two main columns, the first, commanded by Captain General San Martín and supported by Brigadier MajorMiguel Estanislao Soler and BrigadierBernardo O'Higgins, would take the Los Patos Pass and the second, commanded by ColonelJuan Gregorio de las Heras, would take the Uspallata Pass, which at its highest reaches some twelve thousand feet above sea level. Because this second pass was more negotiable, the artillery was taken in the second column.

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