José de San Martín Manuel Rodríguez had returned to Chile before the crossing, and began a guerrilla war in Santiago de Chile against the royalists, in support of the upcoming army. He was supported in the south of the city and the countryside. The strategy was to occupy nearby villages, seize the royalists' weapons and flee. The attacks on Melipilla and San Fernando, and a failed one at Curicó, demoralized the royalists. The columns that crossed the Andes began to take military actions. The column in the north led by Cabot defeated the royalists in Salala, seized Coquimbo and then Copiapó. In the south,
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