Cochrane left the UK in official disgrace, but that did not end his naval career. In May 1817, at the request of Chilean leader Bernardo O'Higgins, he took command of the Chilean Navy in Chile's war of independence against Spain. He was the first Vice Admiral of Chile andCommander-in-Chief of the Chilean Navy.
Accompanied by Lady Cochrane and their two children, he reached Valparaiso on 28 November 1818. Named a vice admiral, Cochrane reorganized the Chilean navy, introducing British naval customs. He took command of the frigate O'Higgins and raided the coasts of Chile andPeru as he had those of France and Spain. He organized and led the capture of Valdivia, despite only having 300 men and two ships to deploy against seven large forts. In 1820, forces under his command cut out and captured the Esmeralda, the most powerful Spanish ship in South America. However, he failed in his attempt to capture the Chiloé Archipelago for Chile. Later, O'Higgins ordered him to lead the Chilean fleet to free Peru from Spain, while Jose de San Martin would lead the Freedom Army. This resulted in Peruvian independence, which O'Higgins considered indispensable to both Chile's independence and security.
Cochrane is alleged to have made plans to free Napoleon from his exile on Saint Helena and make him ruler of a unified South American state. Before he could carry out his plan, Napoleon died in 1821. Cochrane left the service of the Chilean Navy on 29 November 1822.
