The Banda Oriental had been incorporated as a Brazilian Province in 1822, when Brazil became independent from Portugal.

The centralized government, under Brazilian Emperor Pedro I, led to many revolts inside Brazil.

Seeing a chance to break the rule of a foreign nation over their country, some Orientals had raised the flag of rebellion against the Brazilian government in 1825.

At first, the fight did not attract much attention from the Brazilian government, which was dealing with revolts even in Rio de Janeiro at the time.

Nevertheless, as the rebellion spread quickly, Pedro I had had to gather an army by any way that he could to send to "Cisplatina" (the province's name under Brazilian control).

The Army was, at first, led by Pedro I himself, but political problems had forced him to return to the capital without getting close to the battlefield.

By December 1826, the command has been given to General Felisberto Caldeira Brant, Marquis of Barbacena.

By now, the appeal the Orientals sent to Buenos Aires brings Argentina into the conflict.

The Buenos Aires leadership sees a chance to bring the Banda Oriental back into the Argentine Confederation as a province.

General Carlos María de Alvear is appointed as commander of the Republican Army.