- Brooklyn Eckfords (1862-1872)
- New York Mutuals (1868-1876)
- Brooklyn Atlantics (1873-1875)
- Hartford Dark Blues (1877)
- Brooklyn Bridegrooms (1889)
Union Grounds was located in Williamsburg, a suburb of Brooklyn, NY.
Over the years it served as home grounds to a number of baseball teams including: the Brooklyn Eckfords of the National Association (1872 - they also played there as an independent team in 1871); The New York Mutuals of the National Association (1871-1875) and of the National League (1876); the Brooklyn Atlantics of the National Association 1872-1875; and the Hartford Dark Blues of the National League (1877). The ballpark was also used briefly by the Brooklyn Bridegrooms of the American Association in 1889, and as a neutral site by various other teams between 1871 and 1878.
The park was located just across the East River from lower Manhattan and was converted as the Union Skating Club's skating ring in the winter. Built in 1862 for use as a baseball stadium, it was the first enclosed baseball field ever constructed, hence its use by various teams from outside Brooklyn. The outfield was immense, with the fences over 500 feet from home plate. A one-story building stood in right field, 350 feet away from home plate and was in play. The site is now entirely built over and part of a Hasidic Jewish neighborhood along Marcy Avenue.
- Peter Filichia: Green Cathedrals: The Ultimate Celebrations of All 273 Major League and Negro League Ballparks Past and Present, Addison Wesley Publishing Company, 1993.