Admiral of the Fleet Sir Fairfax Moresby GCB (29 November 1786 – 21 January 1877) was a Royal Navy officer. As a junior officer he took part in the unsuccessful expedition to capture Ferrol in Spain during the French Revolutionary Wars. He later saw action during the blockade of Brest during the Napoleonic Wars before becoming commanding officer of a sloop which was sent to the Aegean Sea to defend the population of Malta from pirates; the grateful people presented him with a sword. He then sailed to the Adriatic Sea where he led a naval brigade providing artillery support to the Austrian forces during the siege of Trieste. He went on to be senior naval officer at the Cape of Good Hope and then senior officer at Mauritius, with orders to suppress the slave trade: he concluded the Moresby Treaty with Seyyid Said, the imam of Muscat, restricting the scope of local slave trading and conferring on English warships the right of searching and seizing local vessels.
Moresby later became Commander-in-Chief of the Pacific Station. His main responsibility was to protect British commercial interests in Valparaíso in the face of unrest among the people of Chile. He also took an interest in Pitcairn Islands at this time and planned the emigration of the islanders to Norfolk Island.
Promoted to rear admiral 20 December 1849, Moresby became Commander-in-Chief of the Pacific Station, with his flag in the fourth-rate HMS Portland in August 1850. His main responsibility was to protect British commercial interests in Valparaíso in the face of unrest among the people of Chile. He also took an interest in Pitcairn Islands at this time and planned the emigration of the islanders to Norfolk Island which took place in 1856. Moreover, he proposed the establishment of the Esquimalt Naval Base on the West Coast of Canada, a recommendation which was taken up by the Admiralty in 1860.
Moresby was advanced to Knight Commander of the Order of the Bath on 5 July 1855, promoted to vice-admiral on 12 November 1856 and promoted to full admiral on 12 April 1862. He was advanced again to Knight Grand Cross of the Order of the Bath on 28 March 1865 and appointed Rear-Admiral of the United Kingdom on 20 April 1867 and then Vice-Admiral of the United Kingdom on 17 July 1869. He was promoted to Admiral of the Fleet on 21 January 1870.
Moresby died at his home near Exmouth in Devon on 21 January 1877 and was buried at St Margaret and St Andrew's Church, Littleham. After his death Port Moresby in Papua New Guinea and Fairfax Harbour on which it stands were named after him, as were the Moresby Islands in British Columbia.