The series portrays his career as a physician, naturalist and spy in the Royal Navy during the Napoleonic Wars, and the long pursuit of his beloved Diana Villiers.
Maturin was played by Paul Bettany in the 2003 film Master and Commander: The Far Side of the World and by Nigel Anthony and Richard Dillane in the BBC Radio 4 adaptations of O'Brian's novels.
As a boy he lived in Ireland, fostered by a family of pig-herders in Cahersiveen and County Clare, and spent his teenage years in Catalonia – most notably with his grandmother in Lleida, his uncle in Barcelona and his godfather in Ullastret.
He returned to Ireland in his adolescence, and performed premedical studies at Trinity College Dublin, and received further training in Paris,[1] conceding to have "dissected with Dupuytren"[2] while there.
Being that ships' surgeons in that era usually received very limited training or advanced education, the officers and crew of the Sophie are very pleased to have a true physician on board.
Their esteem for Maturin's medical skill increases early on when he successfully performs delicate surgery on deck, repairing a crew member's serious head injury by removing a damaged portion of his skull and replacing it with a silver coin hammered into a dome by the armourer.
As a passionate advocate of Catalan independence and a resolute opponent of Bonaparte's tyranny, Maturin had become involved in intelligence gathering, and as he begins his career with the Royal Navy, he becomes a valued volunteer secret agent for the Admiralty.
His political and intelligence missions are of such vital importance that Jack Aubrey is often sent to far-flung corners of the world primarily to discreetly allow his apparent ship's surgeon to perform a task for the British government.
While being held by French intelligence agents, Maturin was subjected to the rack (among other implements), making him a temporary invalid and permanently damaging his hands.
Maturin is fluent in Catalan, English, French, Irish, Latin and Spanish, and on his travels, he develops a working knowledge of Greek, Malay, Arabic and Urdu.
His frugal personal habits persist despite a considerable share of prize money earned over the years, and a fortune inherited from his Catalan godfather in The Reverse of the Medal.
He uses part of his fortune to buy the recently decommissioned HMS Surprise, giving its command to Jack Aubrey when he had been framed for stock manipulation and temporarily lost his commission.
This is most poignant when he and his assistant Martin are promised time to explore and collect samples in the Galapagos Islands, which permission is abruptly rescinded when HMS Surprise must sail immediately on information as to where USS Norfolk can be found, the target of Aubrey's mission in The Far Side of the World.
In reviewing the film made from the series of books, Christopher Hitchens finds "the summa of O'Brian's genius was the invention of Dr. Stephen Maturin.
This was the age of Bligh and Cook and of voyages of discovery as well as conquest, and when HMS Surprise makes landfall in the Galapagos Islands we get a beautifully filmed sequence about how the dawn of scientific enlightenment might have felt.