Argentine War of Independence Chile, allied with the Mapuches. On April 4, Argentine Colonel Juan Gregorio de Las Heras had occupied Concepción, but the Royalists retreated to Talcahuano. In early 1818, Royalist reinforcements from the Viceroyalty of Peru arrived, commanded by general Mariano Osorio, and advanced towards the capital. San Martín then turned to scorched earth tactics and ordered the evacuation of Concepción, which he thought was impossible to defend. On 18 February 1818, the first anniversary of the battle of Chacabuco, Chile declared its independence from the Spanish Crown. On March 18, 1818, Osorio led a surprise attack on the joint Argentine-Chilean army,
Battle of Paraguarí Battle of Paraguarí The battle of Paraguarí took place on January 19, 1811, in Paraguarí (Paraguay), between the patriot army led by Manuel Belgrano and the Royalist army located in Paraguay led by Bernardo de Velasco. The battle would end with a Paraguayan victory; but it boosted confidence in the local population to declare themselves independent from both Buenos Aires patriots and royalists months later. At the outbreak of the May Revolution in Buenos Aires, capital of the Viceroyalty of the Río de la Plata, the government emerged from it, called (in Spanish) "Junta Provisional Gubernativa de las Provincias del