The Battle of Pequereque was a clash which took place on 19 June 1813, during the second Upper Peru campaign of the Argentine War of Independence, between scouting forces of the United Provinces Army of the North and the royalist Army of Peru. The republican cavalry of the Army of the North, led by Colonel Cornelio Zelaya, prevailed over the royalists, under the command of Colonel Pedro Olañeta. Background After the capitulation of General Pio de Tristan in the battle of Salta, on 24 February 1813, the United Provinces' Army of the North gained the upper hand not only in northern Argentina, but also in southern Upper Peru (present-day Bolivia). At the same time, the royalists were experiencing a crisis of command, after the resignation of General José Manuel de Goyeneche for personal reasons. The Spanish garrisons reacted with panic after learning of Tristan's defeat and effected a massive withdrawal of their troops from Jujuy and Potosi towards Oruro, in central Upper Peru. During the early days of May the Army of the North reached Potosi, and a forward screen force of about 500 men was deployed along the route to Oruro. These troops, composed of a cavalry regiment of Dragoons, were commanded by Colonel Cornelio Zelaya. The action The vanguard of the republican army advanced gradually from Potosi through the villages of Yocalla, Las Leñas, Tolapaca and Vilcapugio, before establishing their headquarters in the native hamlet of Ancacato, which had been partially destroyed by the royalists. On 17 June, forced by the lack of supplies in Ancacato, a small detachment of Dragoons was sent to Challapata, some 12 km to the southwest, in search of food and other provisions. They were unaware that a royalist regiment of Cazadores, commanded by Colonel Pedro Olañeta, had captured Challapata shortly before. Two days after leaving Ancacato, the detachment was warned by a native that an enemy force was marching along the pass in the opposite direction. Zelaya immediately ordered the build-up of his forces in order to meet the royalists in a battle of encounter. Zelaya appointed one of his officers, Juan Francisco Zamudio, to lead a mounted company to face the advancing royalists, who had seized the small town of Pequereque, at the opposite end of the ravine. In the meantime, an infantry squadron was deployed in the rearguard along the pass, to prevent any hostile infiltration. The remainder of the