Lord Cochrane, on his own initiative, organizes and leads the capture of Valdivia on February 6, 1820, despite only having three hundred men and two ships to deploy against seven large forts.

Having become a citizen of unrecognized Republic of Chile on December 11, 1818, at the request of Chilean leader Bernardo O'Higgins, he had been appointed Vice Admiral and had taken command of the Chilean Navy in Chile's war of independence against Spain.

Cochrane had reorganized the Chilean navy with British commanders, introducing British naval customs and, formally, English-speaking governance in their warships.

Taking command in the frigate O'Higgins, he had blockaded and raided the coasts of Peru, as he had those of France and Spain.