The Battle of Islay (Spanish: Batalla de Islay or Combate Naval de Islay) was a confrontation that occurred on January 12 and 13, 1838, during the War of the Confederation, a conflict between Chile and the Peru–Bolivian Confederation.After the treaty of Paucarpata had been repudiated, the Chilean government again dispatched its fleet, composed of 5 battleships (Aquiles and Arequipeño, the corvettes Libertad and Valparaíso and the Monteagudo) under the command of Robert Simpson, to disrupt Peruvian commerce.