Chummy MacGregor

John Chalmers MacGregor (March 28, 1903 – March 9, 1973), better known as Chummy MacGregor, a pianist and composer, was Glenn Miller’s pianist from 1936-1942. He composed the songs "Moon Dreams", "It Must Be Jelly ('Cause Jam Don't Shake Like That)", "I Sustain the Wings", "Doin' the Jive", "Sold American", and "Slumber Song".

He graduated from the University of Michigan in 1925 and was a member of Delta Tau Delta. Before joining with Glenn Miller, MacGregor played with Irving Aaronson. He played in Glenn Miller’s first unsuccessful band in 1936-37. He remained when Glenn Miller reformed the orchestra that would eventually become the most popular and successful big band. The band would achieve 23 no.1 hits from 1939 to 1943.

He was played by Harry Morgan in The Glenn Miller Story (1953), starring James Stewart and June Allyson, on which he was a consultant and technical advisor.

He was in the Twentieth Century Fox movies Sun Valley Serenade (1941) starring John Payne and Sonja Henie and Orchestra Wives (1942), starring George Montgomery and Ann Rutherford as part of the Glenn Miller Orchestra, both of which featured Glenn Miller and His Orchestra. He is not seen in either movie except for a small scene at the piano when Miller is playing "Chattanooga Choo Choo" because band pianist Ted Scott, played by John Payne, could not make it in time for the rehearsal. He appeared uncredited in Sun Valley Serenade as part of the Glenn Miller Orchestra. He played the piano parts and solos for Cesar Romero in Orchestra Wives.

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