In 1869 the Cincinnati Red Stockings became the first openly all-professional baseball club in the world. The history, geography, demography, and economy of the area contributed to making Cincinnati a baseball town par excellance.

During professional baseball's formative years in the 19th century, Cincinnati was almost always represented by a club called the Reds in one league or another. As chairman of the National Commission after he had helped broker peace between the National and American Leagues, Cincinnati owner Garry Hermann became known as the “Father of the World Series”. The Reds proceeded to win the Series in 1919, 1940, 1975, 1976, and 1990.

Under the ownership of the controversial Marge Schott and managed on the field by the mercurial Lou Piniella, the Reds led the National League West wire-to-wire in 1990, defeated the Pittsburgh Pirates in the National League Championship Series, and swept the powerful Oakland Athletics in the World Series. Stars such as Barry Larkin and Eric Davis, along with pitcher Jose Rijo and the trio of relievers known as the Nasty Boys deserve much of the credit for the Reds' success, but lesser known players, for example, Billy Hatcher and Glenn Braggs, made significant contributions. Although they have come close the Reds have not yet won another pennant since the glorious 1990 season.