Spanish American wars of independence important change in strategy after three United Provinces campaigns had been defeated in Upper Peru. San Martín's army became the nucleus of the Army of the Andes, which received crucial political and material support in 1816 when Juan Martín de Pueyrredón became Supreme Director of the United Provinces. In January 1817, San Martín was finally ready to advance against the royalists in Chile. Ignoring an injunction from the congress of the Río de la Plata not to move against Chile, San Martín together with General Bernardo O'Higgins Riquelme, later Supreme Director of Chile, led the Army over the Andes in
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