Cisplatine War - Aftermath

Aftermath

The stalemate in the Cisplatine War, caused by the destruction of the Argentine fleet, the inability of the Argentine land forces to capture any major cities in Uruguay, the severe economic consequences imposed by the Brazilian blockade of Buenos Aires, and the temporary lack of manpower for a full-scale Brazilian land offensive against Argentine forces, allied to increasing public pressure in Brazil to end the war. All of this motivated the interest on both sides for a peaceful solution.

Given the high cost of the war for both sides and the burdens it imposed on trade between the United Provinces and the United Kingdom, the latter pressed the two belligerent parties to engage in peace negotiations in Rio de Janeiro. Under British and French mediation, the United Provinces of River Plate and the Empire of Brazil signed the 1828 Treaty of Montevideo, which acknowledged the independence of the Cisplatine Province under the name Eastern Republic of Uruguay.

The treaty also granted Brazil sovereignty over the eastern section of the former Eastern Jesuit Missions and, most importantly, guaranteed free navigation of the River Plate – a central national security issue for the Brazilians, but also an issue of great interest to the United Kingdom.

In Brazil, the loss of the Cisplatine Province added to growing discontent with Emperor Pedro I. Although it was far from the main reason, it was a factor that led to his abdication in 1831.