The first two military campaigns ordered by the revolutionary Junta in Buenos Aires are launched against Cordoba, where former Viceroy Santiago de Liniers organizes a counter-revolution, and the Intendency of Paraguay, which does not recognize the outcome of events at the May Revolution.

However, the improvised army gathered by Liniers at Cordoba deserts him before battle, so the former Viceroy attempts to flee to Upper Peru, expecting to join the royalist army sent from the Viceroyalty of Peru to suffocate the revolution at Buenos Aires.

Colonel Francisco Ortiz de Ocampo, who leads the patriot army, captures Liniers and the other leaders of the Cordoba counter-revolution on August 6, 1810, but, instead of executing them as he has been instructed, he sends them back to Buenos Aires as prisoners.

As a result, Ocampo is demoted and Juan José Castelli is appointed as the political head of the army.

On August 26, Castelli executes the Cordoba prisoners and leads the Army of the North towards Upper Peru.