Olivia Mary Manning (March 2, 1908 –July 23, 1980) was a British novelist, poet, writer and reviewer. Her fiction and non-fiction, frequently detailing journeys and personal odysseys, were principally set in England, Ireland, Europe and the Middle East. She often wrote from her personal experience, though her books also demonstrate strengths in imaginative writing. Her books are widely admired for her artistic eye and vivid descriptions of place.

Born in North End, Portsmouth, Manning was educated privately at a small dame school before moving to the north of Ireland in 1916. In Bangor, she attended Bangor Presbyterian School, and while in Portsmouth Lyndon House School, and subsequently Portsmouth Grammar School.  When financial circumstances forced Manning to leave school at sixteen, she worked as a typist, and spent some time as a junior in a beauty salon. A talented artist, she took evening classes at the Portsmouth Municipal School of Art. In May 1928, she had a painting selected for an exhibition at Southsea, and was subsequently offered a one woman show of her works. Manning seemed to be poised for a career as an artist, but she had meanwhile continued her interest in literature and at the age of twenty determined instead to be writer.

Manning's first published works were three serialized detective novels, Rose of Rubies, Here is Murder and The Black Scarab which appeared in the Portsmouth News beginning in 1929 under the pseudonym Jacob Morrow. Between 1929 and 1935 she authored about 20 short stories, including a ghost story that was the first work to be published under her own name, though using initials to obscure her gender.  Manning also wrote two literary novels, neither of which was accepted for publication.  Her first serious novel, The Wind Changes, was published in 1937.

In August 1939, Manning married R.D. Smith ("Reggie"), a British Council lecturer posted in Bucharest, Romania, and subsequently in Greece, Egypt and Palestine as the Nazis over-ran Eastern Europe. Her experiences formed the basis for her best known work, the six novels making up The Balkan Trilogy and The Levant Trilogy, known collectively as Fortunes of War. Manning returned to London after the war and lived there until her death, writing poetry, short stories, novels, non-fiction, reviews, and drama for the British Broadcasting Corporation (BBC).