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,
Army of the North (France) him. Jean-Baptiste Jourdan won the Battle of Wattignies in October. On 17–18 May 1794, the Army of the North won a victory at the Battle of Tourcoing while under the temporary leadership of Joseph Souham. The right wing of the army fought under Jourdan in an important victory at the Battle of Fleurus on 26 June. Soon after this, the Allied position in Flanders collapsed, leading to Austria's loss of Belgium and the extinction of the Dutch Republic in the winter of 1794-1795. During this period, the army was engaged in mopping up operations and sieges. On 25 October 1797,