Battle of Riachuelo

The Battle of Riachuelo (or Battle of the Riachuelo) was a large and decisive naval battle of the Paraguayan War between Paraguay and the Empire of Brazil. By late 1864, Paraguay had scored a series of victories in the war, but on 11 June 1865, its naval defeat by the Brazilians on the Paraná River began to turn the tide in favor of the allies.