Army of the Andes 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"
José de San Martín Freire captured Talca. Las Heras routed royalist outposts in Juncalito and Potrerillos. Bernardo O'Higgins, who came from Los Patos pass, defeated the royalists at Las Coimas. This allowed the main columns to gather at Aconcagua valley, meeting at the slopes of Chacabuco. Royalist commander Rafael Maroto converged his armies on that location as well. Maroto had 2,450 men and 5 pieces of artillery, San Martín had 3,600 men and 9 pieces of artillery. The misdirection that concealed the path of the bulk of the Army allowed San Martín this advantage, as other royalist forces were scattered in other regions of