|John Franklin joined the Royal Navy in 1800. His first ships was H.M.S. Polyphemus, on which he served as a midshipman, taking part in the Battle of Copenhagen on 2 April 1801. Franklin's second appointment was as a midshipman on the expedition to explore the coastlines of Australia in H.M.S. Investigator under the command of his relation Captain Matthew Flinders, who personally trained him in many of the the navigational skills. After his return to England in October 1804, his next appointment was on H.M.S. Bellerophon, on which he saw action as a signal midshipman at the battle of Trafalgar on 21 Oct 1805. In 1807 he was transferred to H.M.S. Bedford, being promoted to lieutenant on 11 February 1808. In September 1814 Franklin was wounded in the shoulder during a diversionary raid undertaken at New Orleans. With the final defeat of Napoleon in 1815, Franklin was discharged on half pay.
In 1818 Franklin was appointed to take part in one of the two Arctic expeditions to search for the North-West Passage. He took command of H.M.S. Trent (under commander David Buchan in H.M.S. Dorothea), in the expedition which aimed to head directly north across the North Pole. On the expedition's return in October 1818, Franklin was soon appointed to lead another Arctic expedition, this time travelling by land, with the aim of surveying the coastline of the North American continent, travelling north along the Coppermine River. This first Arctic land expedition lasted three years (1819-1822), and although it did succeed to a certain degree in its surveywork, it was done so at great cost with the loss of 11 men's lives, 9 of them due to stravation and 2 to fatal shooting incidents. Franklin himself resorted at one stage to eating the leather of old moccasins, earning himself epithet of "The Man Who Ate His Boots". In spite of the expedition's failures, Franklin was able to get Admiralty approval for a second Arctic land expedition (1825-1827), which proved much more successful, following better planning and preparations.
Franklin received a knighthood on 29 April 1829 as well as other honours from the Société de Géographie de Paris and Oxford University. In 1830 he was given command of H.M.S. Rainbow, which was stationed in the Mediterranean to help support and bolster the newly liberated country of Greece. His mission, which lasted 3 years, was largely regarded as having been successful, and he received official recognition of his service, being given the Golden Cross of the Order of the Redeemer from the newly established King Otto of Greece and the Royal Hanoverian Order of the Guelph.With no immediate prospect of further Arctic expeditions, Franklin accepted the offer to become the Lieutenant Governor of Van Diemen's Land, now Tasmania (1837-1843). His governorship is usually regarded as an unsuccessful one, as his lack of administrative experience and his inability to satisfy the competing demands of interested parties meant that he struggled to exert real control and implement progressive reforms. Franklin faced strong opposition from his own colonial administrative officers. The Colonial Secretary, John Montagu, who had largely obstructed whatever initiatives Franklin had tried to take, was dismissed by Franklin, he took his revenge on his return to England by discrediing him and his administration in his appeal to the Secretary of State for the Colonies, Lord Stanley. Franklin was recalled, leaving Hobart in Novemer 1843 and arriving in England in June 1844.
On his return he sought command of an Arctic sailing expedition which was thought would achieve the final link in the search for the North West Passage. In spite of Admiralty misgivings about his age, in Febuary 1845, Franklin was appointed leader of an expedition made up of two specially strengthened ships which had already been successfully used for the Antarctic expedition of Sir James Ross, H.M.S. Erebus and H.M.S. Terror, the latter being captained by Francis Crozier. The ships and their crews, totalling 129 men, were last seen by whalers in Baffin Bay on 26 July 1845.
After a couple of years, the absence of news about the expedition started to raise concerns. From 1848 onwards, several search expeditions were sent out by the Admiralty to look for Franklin, the ships and their crews. Lady Jane Franklin was highly active in campaigning, not only for the Admiralty to continue sending expeditions, but also to lobby American benefactors to organise expeditions, as well as to raise funds and subscriptions to help her finance her own expeditions. Most of these achieved very little in their search for Franklin. Still unaware of Franklin's fate, the Admiralty promoted him to Rear-Admiral in October 1852. The Admiralty effectively considered him dead, as well as his 128 fellow explorers, when they were taken off the naval pay-roll on 31 March 1854. Later in 1854 John Rae came back from an overland expedition with the first news news on the fate of the Franklin expedition, the finding of several artefacts and relics among the local Inuit population and the reporting of Inuit testimony on starving white men travelling overland to find safety and on the discovery of several bodies, with evidence of cannibalism having taken place among the men. An expedition led by Leopold McClintock (and financed by Lady Franklin) finally provided in 1859 written evidence that Sir John Franklin had died on 11 June 1847, while the ships were locked in by ice of King William Island, and that in May 1848 the remaining men decided to leave the ships and try to make their way on foot to safety, travelling south to get to the Back River. The wreck of H.M.S. Erebus was only found in 2014, while that of H.M.S. Terror was found in 2016. The burial place for Franklin is still not known.