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Patrick O'Brian, CBE (12 December 1914 - 2 January 2000), born Richard Patrick Russ, was an English novelist and translator, best known for his Aubrey-Maturin series of sea novels set in the Royal Navy during the Napoleonic Wars, and centred on the friendship of the English naval captain Jack Aubrey and the Irish-Catalan physician Stephen Maturin. The 20-novel series, the first of which is Master and Commander, is known for its well-researched and highly detailed portrayal of early 19th-century life, as well as its authentic and evocative language. A partially finished 21st novel in the series was published posthumously containing facing pages of handwriting and typescript. O'Brian wrote a number of other novels and short stories, most of which were published before he achieved success with the Aubrey-Maturin series.

O'Brian returned to writing after the war, when he moved to rural Wales. His non-fiction anthology A Book of Voyages (1947) attracted little attention. A collection of short stories, The Last Pool, was published in 1950 and was more widely and favourably reviewed, although sales were low. The countryside and people around his village in Wales provided inspiration for many of his short stories of the period, and also his novel Testimonies (1952), which is set in a thinly disguised Cwm Croesor, and which was well received by Delmore Schwartz in Partisan Review in 1952.  In the 1950s O'Brian wrote three books aimed at a younger age group, The Road to Samarcand, The Golden Ocean, and The Unknown Shore. Although written many years before the Aubrey-Maturin series, the two naval novels reveal literary antecedents of Aubrey and Maturin. In The Golden Ocean and The Unknown Shore, based on events of George Anson's voyage around the world from 1740 to 1744, they can be clearly seen in the characters of Jack Byron and Tobias Barrow in the latter novel.  Over four decades he worked on his own writings, his British literary reputation growing slowly. He became an established translator of French works into English. His early novels and several of the translations were published by Rupert Hart-Davis from 1953 to 1974. O'Brian wrote the first of the Aubrey-Maturin series in 1969 at the suggestion of American publisher J.B. Lippincott, following the death of C. S. Forester in 1966, a writer of popular nautical novels. The Aubrey-Maturin books were quietly popular in Britain; after the first four volumes they were not published in the United States.  In the early 1990s the series was successfully relaunched into the American market by the interest of Starling Lawrence of W. W. Norton publishers, attracting critical acclaim and dramatically increasing O'Brian's sales and public profile in the UK and America. Paul D. Colford notes that when O'Brian "visited the United States a few weeks ago, fans waiting to meet, lunch and have tea with him included Walter Cronkite, Sen. Dirk Kempthorne (R-Idaho) and Supreme Court Justice Anthony Kennedy, who invited O'Brian to attend a session of the high court. Hollywood also wants a piece of the press-shy storyteller." The novels sold over 3 million copies in 20 languages. In its review of 21 (published in 2004), Publishers Weekly says that over 6 million copies have been sold. Thus O'Brian's greatest success in writing, gaining him fame, a following and invitations to events and interviews came late in his life, when he was well into his seventies, and accustomed to his private life.  Shortly before his last completed novel was published in October 1999, O'Brian wrote an article for a series of the best in the millennium ending, titled Full Nelson, choosing for his topic Admiral Nelson's victory in the Battle of the Nile in 1798.

What is he most famous for?
greatest success in writing, gaining him fame, a following and invitations to events and interviews came late in his life,