The Battle of Curupayty was a key battle in the Paraguayan War. On the morning on 22 September 1866, the joint force of Brazilian, Argentine, and Uruguayan armies attacked Paraguayan fortified trenches on Curupayty. The Paraguayans were led by general José Eduvigis Díaz. This position was held by 5,000 men and 49 cannons, some of them in hidden places out of the attackers view. The Imperial Brazilian Navy gave support to the 20,000 assailants, but the ships had to keep some distance from the guns at the fortress of Humaitá, which led to the lack of accuracy and impact of the ship's fire. The navy's failure was crucial at the later ground battle result.
The Battle of Curuzú occurred between September 1 and 3, 1866 during the Paraguayan War. After the first Battle of Tuyutí, won by the Allies on 24 May 1866, an Allied council of war decided to use their navy to bombard and capture the Paraguayan battery at Curupayty.
The Passage of Humaitá was an operation of riverine warfare during the Paraguayan War − the most lethal in South American history − in which a force of six Imperial Brazilian Navy armoured vessels was ordered to dash past under the guns of the Paraguayan fortress of Humaitá. Some competent neutral observers had considered that the feat was very nearly impossible.
The steam corvette Jequitinhonha was a warship in the Imperial Brazilian Navy during the Paraguayan War. It took part in the Battle of Riachuelo.
The Battle of Jaguarí was a naval confrontation in the Paraguayan War between Brazilian and Paraguayan flotillas, which took place on March 23, 1866 at the mouth of the Jaguari River, Paraná River. At the time, aboard the steamer Cisnei, were admiral Joaquim Marques Lisboa and generals Osório, Mitre and Flores. The ship was escorted by the ironclad Tamandaré and the gunboats Beberibe and Henrique Martins, and was on a reconnaissance mission on the Paraná River to the mouth of Jaguari. However, at eleven o'clock in the morning, the Paraguayan steamer Gualeguai and a towed boat found the Brazilian flotilla in Jaguari and immediately started bombing them, without causing damage. Only Tamandaré ran aground on the island of Itapiru. Despite the confrontation, the region's recognition proved to be useful to the allies, as the future location for the landing of the Triple Alliance troops that would initiate the invasion of Paraguayan territory was defined.
The Battle of Paso de Patria was a battle of the Paraguayan War, which took place between April 16 to 23, 1866, on the banks of the Paraná River, in the then fortified position in Paso de Patria, in which the Empire of Brazil emerged victorious. It took place simultaneously with the Battle of Itapirú, during the so-called "crossing of the Paraná River".
The Battle of Itapirú took place during the Paraguayan War on April 17, 1866, after Brazil's capture of Purutué Bank a week earlier. The battle marked the beginning of the Triple Alliance's invasion of Paraguay.
The Assault of Paso Cidra was an allied military operation during the Paraguayan War, which took place on May 20, 1866, in Estero Bellaco, Paraguay. The action consisted of the assault by Brazilian forces of the 2nd Infantry Battalion, under the command of Vanderlei Lins, subordinate of Uruguayan general Venâncio Flores, to a Paraguayan entrenched position, defended by men of Lieutenant Colonel Avelino Cabral. The operation was successful, with taking the position and clearing the path for the Allied march.
The Battle of Palmar was a confrontation of the Paraguayan War between a squad of the Brazilian Armada and army troops against a group of Paraguayan soldiers on the Paraguay River, fought on September 2, 1866 and which resulted in victory for the allies.
The Battle of Arroio Hondo, also known as Combat of Penimbu or Puru-Hué (Peru-Huê), took place on 3 August 1867, during the Paraguayan War.
The Battle of Perecué, also known as Battle of Tayí Island, was an armed action that occurred during the Paraguayan War. Paraguayan general Bernardino Caballero's troops launched guerrilla-style raids on the Allied encampment in the Tayí area, near the Humaitá Fortress. The Marquis of Caxias, Luís Alves de Lima e Silva, who had replaced Bartolomé Mitre in the supreme command of allied troops, learned of the Paraguayan presence in the area and prepared a counterattack on his enemies, failing in this action that resulted in a pyrrhic victory of the Paraguayans.
The Battle of Estero Rojas took place on 24 September 1867, when a Brazilian convoy, coming from Tuyutí to Tuju-Cuê, was attacked by Paraguayan troops under the command of Vallois Rivarola.
The Battle of Villa del Pilar took place during the Paraguayan war. Brazilian forces, under the command of then Colonel Rufino Eneias Gustavo Galvão, advanced on the village on September 20, 1867. About 250 Paraguayan soldiers resisted the attack, and Francisco Solano López ordered Colonel Felipe Toledo to send aid. There were 300 Brazilian casualties against 174 of the Paraguayans.
The Battle of Paso Ipohy was an action planned by the Paraguayans that consisted of a surprise attack on a Brazilian camp near Humaitá, near the Tebicuary River in Paraguay, on December 25, 1867. The attack resulted in the victory of the outnumbered Paraguayans.
The assault on the battleships Cabral and Lima Barros was a naval action that took place at dawn on 2 March 1868, during the Paraguayan War, when Paraguayan canoes, yoked two by two, disguised with branches and with 50 soldiers each, approached the Brazilian ironclads Lima Barros and Cabral.
The Brazilian ironclad Cabral was a Cabral-class armored corvette-type warship operated by the Imperial Brazilian Navy from 1866 to 1882. The vessel was built in the shipyard of the British company J. and G. Rennie in Greenwich, England, and was the leader of its class, which also included Colombo. It was launched in 1865 and incorporated into the navy on 15 September 1866. The battleship was entirely made of iron and displaced 858, 1,033 or 1,050 tons, depending on the source. It had two steam engines that developed up to 750 hp, propelling the vessel at about 20 km/h. Its structure comprised a double pillbox with eight gunports. The navy had great difficulties with this ship, which was hard to navigate and, due to the design of its casemate, which left a part of it unprotected, it was vulnerable to diving projectiles.
The assault on the battleship Barroso and the monitor Rio Grande, also known as assault on the battleships at Tagy, was a Paraguayan naval operation carried out during the Paraguayan War. The Imperial Brazilian Navy was present in the main actions of the allied forces. President Francisco Solano López knew of the threat that the navy posed and wanted to capture some of its ships, the ironclads. The seizure was also seen as a form of compensation for the losses incurred as a result of the war. Assault plans were created and executed in 1868.
The Brazilian ironclad Colombo was a Cabral-class armored corvette-type ironclad operated by the Imperial Brazilian Navy between 1866 and 1875. The vessel was built in the shipyard in Greenwich, England, by the British company J. and G. Rennie, along with her sister ship Cabral. It was launched in 1865 being commissioned on 4 July 1866. The battleship was entirely made of iron, displacing 1,069 tons. It had two steam engines that developed up to 750 HP of power, propelling the vessel at about 20 km/h. Its structure comprised a double casemate with eight gunports. The Brazilian navy had great difficulties with this ship, which was hard to navigate and, due to the casemate's model, had an unprotected section, which was vulnerable to diving projectiles.
Mariz e Barros was an ironclad, or armored corvette, of the Mariz e Barros class operated by the Imperial Brazilian Navy. The ship was originally built for the Paraguayan Navy, but was not delivered as the country was unable to pay due to the Paraguayan war. The Empire of Brazil eventually acquired her in 1865, and she was renamed Mariz e Barros in honor of Lieutenant-Captain Antônio Carlos de Mariz e Barros, who died in battle.
The Passage of Fortín Island consisted of the transposition carried out by a naval division of the Imperial Brazilian Navy - consisting of the ironclads Bahia and Silvado, and the monitor Alagoas - against a Paraguayan fortified position located near the Fortress of Humaitá called Fortín Island, on the banks of the Paraguay River, on 24 July 1868, during the Paraguayan War. The passage was successfully completed, even under fire from the fortifications. At night, the Paraguayans left Fortín Island to Acayuazá and Isla Poí.
Uruguay 
Joaquim José Inácio 
Solano López 
