The Marvelettes record their debut single in April of 1961 at Berry Gordy’s Hitsville U.S.A. studio in Detroit—home of Motown. Released on Aug. 21, 1961, on Motown subsidiary label Tamla, it reaches the top of the Billboard Hot 100 pop singles chart on Dec. 11, 1961, thus becoming Motown’s first number-one pop hit. It is also thus Motown’s first number-one pop hit on which the label’s main house bassist, James Jamerson, plays. What was the song?
Update: And the answer is “Please Mr. Postman”