Battle of Riachuelo

Battle of the Riachuelo
Part of the Paraguayan War
The Battle of Riachuelo by Pedro Américo
Date June 11, 1865 Location Riachuelo stream, Corrientes Province, Argentina Result Decisive Brazilian victory
Belligerents
Paraguay Paraguayan Army Paraguayan Navy	Empire of Brazil Imperial Navy Marine Corps
Commanders and leaders
(WIA)	Baron of Amazonas
Strength
7 ships and 7 barges with 38 guns, 22 cannons on land, 2 congreve batteries 2 Corvettes 7 Steamboats 7 Barges	9 ships with 58 guns 1 Frigate 4 Corvettes 4 Gunboats
Casualties and losses
750 casualties 4 steamers sunk 7 barges sunk	104 killed, 123 wounded, 20 missing 1 corvette sunk

The Battle of the Riachuelo was the biggest naval battle of south-amerian history and a key point in the Paraguayan War. By late 1864, Paraguay had scored a series of victories in the war; on June 11, 1865, however, its naval defeat by the Brazilian Empire on the Paraná River began to turn the tide in favor of the allies.

The Paraguayan fleet was a fraction of the size of Brazil's, even before the battle. It arrived in Humaitá on the morning of June 9. Paraguayan president Francisco Solano López prepared to attack at Riachuelo the ships supporting allied land troops. Nine ships and seven cannon-carrying barges, totaling 45 guns, plus 22 guns and two Congreve rocket batteries from shore troops, attacked the Brazilian squadron, totaling 58 guns. Paraguay planned to attack before sunrise since most Brazilian troops would leave the steamers in order to sleep on land, leaving thus very few men to guard and handle their fleet. The original plan had been that, under the cover of the night, the Paraguayan steamers would approach the docked Brazilian ones and board them. No confrontation other than the one carried out by the boarding party was planned, and the Paraguayan steamers were only there to provide cover from the inland forces.

The Paraguayan fleet left Humaitá on the night of June 10, 1865, headed to the port of Corrientes. López had given specific orders that they should stealithly approach the docked Brazilian steamers before sunrise and board them, thus leaving the Brazilian ground forces bereft of their navy early on during the war. For this, López sent nine steamers: Tacuarí, Ygureí, Marqués de Olinda, Paraguarí, Salto Guairá, Rio Apa, Yporá, Pirabebé and Yberá; under the command of Captain Meza who was aboard the Tacuarí. However, some two leagues after leaving Humaitá, upon reaching a point known as Nuatá-pytá, the engine of the Yberá broke down. After losing some hours in an attempt to fix it, it was decided to continue with only the remaining 8 steamers.

The fleet arrived at Corrientes after sunrise, however, due to a dense fog, the plan was still executable since most, if not all, Brazilian forces were still on land. However, not following López' orders, Captain Meza ordered that instead of approaching and boarding the docked steamers, the fleet was to continue down the river and fire at the camp and docked vessels as they passed by. This new course of action proved catastrophic.

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Wikipedia