Margaret Marian McPartland OBE (née Turner; 20 March 1918 – 20 August 2013), was an English and American jazz pianist, composer, and writer. She was the host of Marian McPartland's Piano Jazz on National Public Radio from 1978 to 2011.

After her marriage to trumpeter Jimmy McPartland in February 1945, she resided in the United States when not travelling throughout the world to perform. In 1969, she founded Halcyon Records, a recording company that issued albums for 10 years. In 2000, she was named a National Endowment for the Arts Jazz Master. In 2004, she was given a Grammy Award for lifetime achievement. In 2007, she was inducted into the National Radio Hall of Fame. Although known mostly for jazz, she composed other types of music as well, performing her own symphonic work A Portrait of Rachel Carson with the University of South Carolina Symphony Orchestra in 2007. In 2010, she was named a member of the Order of the British Empire.

Margaret Marian Turner was born on 20 March 1918 to Frank and Janet (née Payne) Turner in Slough, Buckinghamshire, west of central London, England. She had one younger sibling, a sister, Joyce. She demonstrated early aptitude at the piano, and would later realize that she had perfect pitch. Margaret (Maggie to her family) studied violin from the age of nine, but never took to the instrument. She also trained as a vocalist and received a number of favorable reviews in the local paper. Janet refused to find her daughter a piano teacher until the age of 16, by which time Margaret was already adept at learning songs by ear. This lack of early education meant that Margaret was never a strong reader of notated music, and would always prefer to learn through listening.

Turner studied at Miss Hammond's School for Young Children from 1924 to 1927, Avonclyffe from 1927 to 1929, Holy Trinity Convent from 1929 to 1933, and finally Stratford House for Girls from 1933 to 1935. There, she met Doris Mackie, a teacher who would be hugely influential on her. Mackie suggested to the Turners that Margaret should apply to the Guildhall School of Music and Drama in London, since she clearly had an aptitude and passion for music. She was accepted in the spring of 1935 on the merit of her "rampant enthusiasm, God-given faculty, and a dangerous surplus of imagination" and in spite of the fact that she was "sadly lacking in technique."

Turner pursued studies at the Guildhall School of Music and Drama in London, where she worked toward a performance degree that would enable her to become a concert pianist, though she also did coursework in vocal performance. She studied with Orlando Morgan, who also taught Myra Hess. Turner's talents for improvisation and composition were recognized early when she won the Wainwright Memorial Scholarship for Composition, the Worshipful Company of Musicians Composition Scholarship, and the Chairman's School Composition Prize in 1936 and 1937. Much to her family's dismay, she developed a love for American jazz and musicians such as Duke Ellington, Fats Waller, Teddy Wilson, and Mary Lou Williams, among others. In 1938, Turner sought out Billy Mayerl at his School of Modern Syncopation to seek lessons, and was convinced to audition for his piano quartet. Despite her family's efforts to keep her at Guildhall, Turner left to join Billy Mayerl's Claviers, a four-piano vaudeville act. There, she elected to perform under the stage name of Marian Page. She promised her family that she would one day return to finish her degree at Guildhall. After the Claviers tour, Marian returned to London in the fall of 1938 and played sporadically for shows and on the Carroll Lewis Show. To avoid conscription during World War II, she volunteered for the Entertainment National Service Association (ENSA), a group that was playing for Allied troops, in fall 1940. In 1944, her friend Zonie Dale recommended that Marian join the United Service Organizations (USO) because they paid more and played with American men.

With the USO, Marian went through basic training and was issued a set of combat gear – GI boots, helmet, and uniform. Marian was assigned to a group called the Band Wagon, which followed the Allied forces after the D-Day invasion. In anticipation of wartime demands, Marian learned to play the accordion in the event that there was no piano available with which to play for the troops.

In St Vith, Belgium, on 14 October 1944, Marian met a Chicago cornetist named Jimmy McPartland at a jam session. McPartland had volunteered for the army and was serving active duty when his superiors realized that he could do better work as an entertainer, since he was well known among the troops. Jimmy was solicited to put together a sextet to entertain the troops, and invited Marian to join him as their pianist. They soon fell in love, and signed an official US Army marriage document on 14 December 1944. They married on 3 February 1945, in Aachen, Germany, and played at their own military base wedding. Her marriage to an American male automatically gave Marian US citizenship, side by side with her British citizenship. Marian was reluctant to tell her parents of the marriage, and had Jimmy's commanding officer tell them when he had lunch with them in England in early 1945. It was with Jimmy that Marian began her first real training in jazz. Jimmy and Marian did their first recording together on 6 January 1946 in London before leaving for the US. They arrived in New York City on 23 April 1946, and Marian would never live outside of the US again. However, she kept her British citizenship throughout her life.

After the war, Marian and Jimmy moved to Chicago to be near his family. Jimmy was raised in the Austin neighborhood of Chicago, and was an original member of the Austin High Gang that played Chicago-style Dixieland jazz in the 1920s. In June 1946, Marian made her American debut at the Moose Lodge. Soon, Jimmy's group, which now included Marian, landed a standing gig at the Rose Bowl through the end of 1946. This engagement was followed by ones at Taboo, Capitol Lounge, and finally Brass Rail. Marian flourished in Jimmy's group, and by her association with him. They played at clubs like Blue Note and Silhouette with stars like Billie Holiday.