Long John Silver is a cunning and opportunistic pirate who was quartermaster under the notorious Captain Flint. Stevenson's portrayal of Silver has greatly influenced the modern iconography of the pirate.  Silver has a parrot, named Captain Flint in honor—or mockery—of his former captain, who generally perches on Silver's shoulder, and is known to chatter pirate or seafaring phrases like "Pieces of Eight", and "Stand by to go about". Silver uses the parrot as another means of gaining Jim's trust, by telling the boy all manner of exciting stories about the parrot's buccaneer history. "'Now that bird,' Silver would say, 'is, maybe, two hundred years old, Hawkins—they lives forever mostly, and if anybody's seen more wickedness it must be the devil himself. She's sailed with England—the great pirate Cap'n England. She's been at Madagascar, and at Malabar, and Surinam, and Providence, and Portobello... She was at the boarding of the Viceroy of the Indies out of Goa, she was, and to look at her you would think she was a baby."
Silver claims to have served in the Royal Navy and lost his leg under "the immortal Hawke". "His left leg was cut off close by the hip, and under the left shoulder, he carried a crutch, which he managed with wonderful dexterity, hopping about upon it like a bird. He was very tall and strong, with a face as big as a ham—plain and pale, but intelligent and smiling." .
He also claims to have been the only man whom Flint ever feared. Like many of Stevenson's characters, there is significant duality in the character; ostensibly Silver is a hardworking and likeable seaman, and it is only as the plot unfolds that his villainous nature is gradually revealed. His relationship with Jim Hawkins, the novel's protagonist and narrator, is interesting, as he serves as a mentor and eventually father-figure to Jim, creating much shock and emotion when it is discovered that he is in charge of the mutiny, and especially when Jim must confront and fight him later on.
Although willing to change sides at any time to further his own interests, Silver has compensating virtues: he is wise enough to pay attention to money management, in contrast to the spendthrift ways of most of the pirates, and is physically courageous despite his disability; for instance, when Flint's cache is found to be empty, he coolly stands his ground against five active seamen despite having only Jim, a boy in his teens, to back him.
When Silver escapes at the end of the novel, he takes "three or four hundred guineas" of the treasure with him, thus becoming one of only two former members of Captain Flint's crew to get his hands on a portion of the recovered treasure; a separate cache of bar silver is apparently left on the island. (The repentant maroonee Ben Gunn is the other, but he spends all £1,000 in nineteen days.) Jim's own ambivalence towards Silver is reflected in the last chapter, when he speculates that the old pirate must have settled down in comfortable retirement: "It is to be hoped so, I suppose, for his chances of comfort in another world are very small."
Silver is married to a woman of African descent, whom he trusts to manage his business affairs in his absence and to liquidate his Bristol assets when his actions make it impossible for him to go home. He confides in his fellow pirates, that he and his wife plan to rendezvous after the voyage to Skeleton Island is complete and Flint's treasure is recovered, at which point Silver will retire to a life of luxury. Ironically his "share" of Flint's treasure (£400) is considerably less than that of Ben Gunn's share (£1,000) and what he himself boasts is his "share" from England (£900) and from Flint (£2,000).
According to Stevenson's letters, the idea for the character of Long John Silver was inspired by his real-life friend William Henley, a writer and editor. Stevenson's stepson, Lloyd Osbourne, described Henley as "...a great, glowing, massive-shouldered fellow with a big red beard and a crutch; jovial, astoundingly clever, and with a laugh that rolled like music; he had an unimaginable fire and vitality; he swept one off one's feet". In a letter to Henley after the publication of Treasure Island Stevenson wrote: "I will now make a confession. It was the sight of your maimed strength and masterfulness that begot Long John Silver...the idea of the maimed man, ruling and dreaded by the sound, was entirely taken from you".
British historian Dennis Judd presents Silver as the main character in his 1977 prequel, The Adventures of Long John Silver, and in the 1979 sequel, Return to Treasure Island.
John Silver is also the protagonist in Björn Larsson's fictional 1995 autobiography, Long John Silver: The True and Eventful History of My Life of Liberty and Adventure as a Gentleman of Fortune and Enemy to Mankind, published in Sweden in 1995.
Silver is the main character in Edward Chupack's 2008 Silver — My Own Tale as Told by Me with a Goodly Amount of Murder.[full citation needed]
There have been several major stage adaptations made. The number of minor adaptations remains countless.
For a time, in London, there was an annual production of the musical Treasure Island, based on a book by Bernard Miles and Josephine Wilson. The music was composed by Cyril Ornadel and the lyrics by Hal Shaper. The musical was performed at the Mermaid Theatre, originally under the direction of Bernard Miles, who played Long John Silver, a part he also played in various television versions. Comedian Spike Milligan would often play Ben Gunn in these productions, and in 1981, Tom Baker played Long John Silver.
Peter Wyngarde played Silver in the 1958 TV series The Adventures of Ben Gunn.
BBC Television has presented the story in miniseries format four times, with the role of Silver being played by Bernard Miles in 1951 and again in 1957;, Peter Vaughan in 1968; and Alfred Burke in 1977. Miles played the role one final time in a 1982 TV movie.
In 1959, Ivo Garrani played Silver in an Italian television miniseries.
Ivor Dean played the character in an acclaimed European four-part mini-series in 1966. He intended to reprise the role in another series with more adventures of Silver and began writing it with director Robert S. Baker, but his sudden death in 1974 stopped all further plans. In 1985, the Ivor Dean script was used as foundation for the Disney 10-part TV series Return to Treasure Island, starring Brian Blessed as Long John Silver.
Luke Arnold played John Silver in the Starz television series Black Sails (2014–2017), a prequel story set 20 years before Treasure Island. In this series, Silver as a young man begins as a scheming cook who rises to serve as quartermaster on the Walrus and on a captured Spanish Man O' War, later to lead the pirate and former-slave forces that attempt to re-take Nassau from the British.
^Masefield, John (1921) . Salt-Water Poems and Ballads. New York, NY: The Macmillan Company. pp. 64–65. Retrieved February 21, 2017. Masefield's original 1902 work was entitled Salt-Water Ballads.