Battle of Rancagua Battle of Rancagua The Battle of Rancagua also known as the Disaster of Rancagua occurred on October 1, 1814, to October 2, 1814, when the Spanish Army under the command of Mariano Osorio defeated the rebel Chilean forces led by Bernardo O’Higgins. This put an end to the Chilean Patria Vieja and it was the beginning of the Spanish Reconquista of South America. When Spain heard about the Patriot revolt in Chile, they sent an army of Spanish soldiers and royalists to defeat the rebellion. When O'Higgins heard about the besieged army in Rancagua, he went with his army of
José de San Martín Nearly 700 expeditionary soldiers of New Granada deserted and joined the patriots. Several populations in the north of Peru supported San Martín, and Arenales defeated the royalists at the Battle of Pasco. More than 300 royalists joined the patriots, including Andrés de Santa Cruz. However, the plans did not fully work as intended. The native populations that joined Arenales could not resist the royalist counter-attacks, and the slaves did not join the army in the expected numbers. The Argentine provinces could not send the supporting army that San Martín had requested earlier, and the Army of the North no longer