The original single was credited to Inez Foxx with vocal accompaniment by her brother Charlie, as they alternated the lyric on a syllabic basis. Considered something of a novelty song, it was a great success for them upon its release by Sue Records (Symbol Records), reaching number 2 on the U.S. Top Black Singles / Rhythm & Blues chart and number 7 on the U.S. popular music singles chart in late summer 1963.Chris Blackwell of Island Records company heard "Mockingbird" playing in a record store in Kingston, Jamaica and flew to New York City to negotiate the track's UK release; resultantly Island Records leased the Sue brand for UK distribution in order to vend the American company's output in the UK, beginning with "Mockingbird" in December 1963. However "Mockingbird" would not become a UK success until its 1969 re-issue when it scored #33.

The song was covered by Dusty Springfield for her 1964 album A Girl Called Dusty; Springfield sang both parts of the track. "Mockingbird" was also recorded by Aretha Franklin for her 1965 album Runnin' Out of Fools; Franklin performed "Mockingbird"—with Ray Johnson providing the counter-vocal—on the 10 March 1965 episode of the program Shindig. Franklin's version of "Mockingbird" was one of several tracks to which Columbia Records company gave a single release after the singer's commercial success with Atlantic Records in 1967; released at the same time as Franklin's Atlantic single album "Chain of Fools"—which would reach #2—Franklin's version of "Mockingbird" scored two weeks at #94 on the Billboard Hot 100 in December 1967.

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