Concepción, Chile Santiago on September 18, 1810, citizens of Concepción joined up. Concepción was used as the point of entry by the Spanish Army in the attempt by the Viceroyalty of Peru to re-conquer Chile. Concepción politicians and soldiers became a significant political force in the newly independent country. On January 1, 1818, Ambrose O'Higgins's son, Bernardo O'Higgins, proclaimed and took the oath of the Chilean War of Independence in the main square of Concepción, which since then has been known as "Plaza de la Independencia". On February 20, 1835, the town again was largely destroyed by an earthquake and had to
José de San Martín that it was not possible to defend Concepción, so he ordered O'Higgins to leave the city. 50,000 Chileans took cattle and grain and moved north, burning everything else, so that they did not leave supplies for the royalists. As he had done with the Tucumán Congress, San Martín urged a declaration of independence, to legitimize the government and the military actions. The Chilean Declaration of Independence was issued on 18 February 1818, one year after the battle of Chacabuco. San Martín, Las Heras and Balcarce met in Curicó, and the royalists in Talca, in a plain known as "Cancha rayada".