This victory was a significant defeat for the Captaincy General of Chile, the royalist government established after the division of the Viceroyalty of Peru.

In 1814, after helping establish a popularly elected congress in Argentina, José de San Martín began considering how to expel the Spanish royalists from South America entirely.

Thanks to his careful planning, the royalist forces in Chile were misled into defending against threats that didn’t exist, allowing his crossing to go unchallenged.

However, despite this strategic advantage, the Army of the Andes, as San Martín's force was known, suffered severe losses during the crossing, losing as much as one-third of its men and more than half of its horses.

A force of around 1,500 men, led by Brigadier Rafael Maroto, moved to block San Martín's advance at Chacabuco, a valley near Santiago.

Facing the crumbling state of the royalist forces, Maroto initially proposed abandoning the capital and retreating south, where they could regroup and gather resources for a renewed campaign.

During a military conference called by Royal Governor Field Marshal Casimiro Marcó del Pont on February 8, Maroto's strategy was adopted.

The night before the battle, Antonio de Quintanilla, who would later distinguish himself in the defense of Chiloé, privately expressed his doubts about the strategy.

San Martín received numerous reports on the Spanish plans from a spy disguised as a roto, a poverty-stricken Chilean peasant.

The roto informed him that the Spanish general, Marcó, was aware of fighting in the mountains and had ordered his army to "run to the field," referring to Chacabuco.

Continental Significance: The Battle of Chacabuco thus served as a turning point in the Chilean War of Independence, laying the groundwork for future victories and the eventual liberation of Chile and other regions from Spanish colonial rule.