The franchise is named for the "Star-Spangled Banner" writer Francis Scott Key, a native of Frederick County.

Frederick players from this era who were major leaguers: The team was founded in 1989 when the Baltimore Orioles decided to move their Class A Carolina League affiliate from Hagerstown, Maryland.

[7] The Keys opened by losing both ends of a doubleheader (including a seven-inning perfect game by Dennis Burlingame) against the Durham Bulls.

On June 11, 2005, Jeff Fiorentino's contract was purchased by the Orioles in order to replace the injured Luis Matos.

In their inaugural season, the opening day roster featured several future major leaguers: David Segui, Francisco de la Rosa, Luis Mercedes, Jack Voigt, and Pete Rose Jr.[10] Other Keys alumni include: Pitchers Catchers Infielders Outfielders