William James Finegan, known as Bill Finegan, was an influential American jazz bandleader, pianist, arranger, and composer born on April 3, 1917, in Newark, New Jersey. He grew up in Rumson, New Jersey, where he attended Rumson-Fair Haven High School and taught orchestration to his schoolmate, Nelson Riddle. Finegan studied piano with Elizabeth Connelly and musicianship with flautist/alto saxophonist Rudolph John Winthrop. He furthered his musical education at the Paris Conservatory and studied with notable figures such as Stefan Wolpe, Darius Milhaud, and Valérie Soudères.

Finegan's career took off when he became a staff arranger for the Glenn Miller Orchestra in the late 1930s, arranging hits like "Little Brown Jug" and "Song of the Volga Boatmen." He also arranged music for films such as "Sun Valley Serenade" and "Orchestra Wives." After his time with Miller, he worked with Tommy Dorsey from 1942 to 1952, contributing to the film "The Fabulous Dorseys."

In 1952, Finegan co-founded the Sauter-Finegan Orchestra with Eddie Sauter, known for its innovative and unconventional sound. The orchestra was active until 1957, and Finegan's arrangement of "Doodletown Fifers" became one of their best-known pieces. Following the orchestra's disbandment, Finegan worked in advertising, writing music for commercials, and continued arranging for various ensembles, including the Glenn Miller Orchestra and Mel Lewis's orchestra.

Finegan also taught jazz at the University of Bridgeport in the 1980s and wrote arrangements for cornetist Warren Vaché and the vocal group Chanticleer until his death on June 4, 2008, in Bridgeport, Connecticut, at the age of 91. He was survived by his wife Rosemary O'Reilly Finegan, their son James, and daughter Helen.