The Fireflies were an American doo wop group from Philadelphia, Pennsylvania. The group formed in Philadelphia in 1957, and underwent several lineup changes over the course of their existence; its most prominent member was Ritchie Adams. The group was produced by Gerry Granahan. Their debut for Roulette Records was the single "The Crawl", but the group's second single, the Ribbon Records release "You Were Mine", was their biggest hit. It peaked at #21 on the Billboard Hot 100 in 1959.[1] Following the single's success, The Paulette Sisters released an answer record called "I Was Yours", and Wayne Thomas covered "You Were Mine".[2]

Later singles included "I Can't Say Goodbye", "Marianne", and "My Girl" (all 1960); "I Can't Say Goodbye" was the only charter, peaking at #90 in the U.S..[1] In 1962 the group reappeared on Taurus Records with "You Were Mine for Awhile" and "Blacksmith Blues" on Hamilton Records; three other singles followed on Taurus, but the group never returned to the charts. The group lasted as long as 1967 before disbanding for good.

Adams went on to release some solo singles and had a highly successful songwriting career. Granahan had a solo hit the same year The Fireflies had their only Top 40 hit.

The original members involved in the song "You Were Mine" in 1959 were Paul Giacalone, Richie Adams, Lee Reynolds, John Viscelli, Carl Girosli. Background singers also included Jerry Granahan and the Perone Sisters. The songs "You Were Mine" and "I Can't Say Goodbye" were both written by Paul Giacalone.