"Hang On Sloopy" is a 1964 song by Wes Farrell and Bert Berns, originally titled "My Girl Sloopy". It peaked at number 1 on the US Billboard Hot 100.

According to Rick Derringer, the original version of Sloopy was written by a "high school kid in St. Louis" and sold to Bert Russell, a.k.a. Bert Berns. If true, the answer to the age old question "Just who is Sloopy?" lies with him. Dorothy Sloop, A jazz singer from Steubenville, Ohio and a student at Ohio University, is noted to be the inspiration for the song. "My Girl Sloopy" was first recorded by L.A.-based The Vibrations in 1964, for Atlantic Records (45-2222), reaching #10 on the R&B chart and #26 on the US pop chart. In April 1965 the song became a local hit in the Pacific Northwest in a cover version by James Henry & The Olympics (Jerden Records), but it was quickly eclipsed in August when the Indiana pop group The McCoys released their iconic retitled version. "Hang On Sloopy" went to #1 in the United States in October 1965.

In early 1965, The Strangeloves, a New York City rock band, wanted to make the song the follow-up to their hit single "I Want Candy" and began performing the song in concert. However, the Dave Clark Five, with whom they were touring, told the Strangeloves that they were going to record their own version of the song when they returned to England, copying the Strangeloves' crowd-pleasing arrangement. The Strangeloves realized that the Dave Clark Five's version would probably outsell their own, but they weren't ready to release a new single yet because they were still enjoying the success of "I Want Candy" from a couple months earlier. The answer presented itself when a young rock group named Rick and the Raiders opened for (and provided backing for) The Strangeloves in July in Dayton, Ohio. The Strangeloves — who were, in reality, three successful writer/producers from Brooklyn, New York — recruited Rick and The Raiders to release the song under their name. Their 16-year-old leader, Rick Zehringer, was flown to New York to record his lead vocal over The Strangeloves' already-recorded backing tracks. It was decided to change the name of Rick's group to The McCoys to avoid confusion with another popular band of the era, Paul Revere & the Raiders, and Rick himself began using the stage name Rick Derringer. The single was released on Bang Records and entered the chart on August 14, 1965, effectively beating the Dave Clark Five to the charts. The single went on to hit number one on October 2.

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