BAP Unión (1865)

During the American Civil War, the Confederate States ordered the French shipbuilder Henri Arman de Rivière to build 4 cruisers. He built 2 in his own shipyard in Bordeaux, under the names of Osaka and Yedo, which were to be called Louisiana and Mississippi. The other two were commissioned from his partner Voruz in Nantes, under the names of San Francisco and Shanghai, which were to be called Texas and Georgia. Due to pressure from American diplomacy, the cruisers were embargoed in 1864 when they were not yet completed. Those in Bordeaux were bought by Prussia, then at war with Denmark, while those in Nantes were bought by Peru in anticipation of a possible war with Spain.

Peru bought the two vessels in November 1864 at a cost of 2.3 million francs, equivalent to 92 thousand pounds sterling, which was more than the Huáscar monitor cost. The San Francisco took the name of America and the Shanghai became the Union. Lieutenant Commander Juan Pardo de Zela took command of the America and First Lieutenant Miguel Grau was assigned to the Union. Both corvettes, which were in Saint Nazaire, prepared to set sail for the Pacific in December 1864.

Under the command of Manuel Villavicencio the Union was tasked with breaking the Blockade of Arica in order to deliver supplies to the beleaguered city.

The operation was a success with the vessel breaking the Arica blockade twice. It's casualties were several wounded and one dead.

The Union arrived in Callao on March 20.

The Chilean Navy began the Blockade of Callao in the early hours of 10 April 1880 which led to the Union being trapped.

on 16 January 1881, the Union and other ships of the Peruvian Navy were sunk in Callao to prevent them from falling into Chilean hands.