Harlem Globetrotters
They were founded in 1925 in Chicago.  Almost all their players are African-American, which was unusual at the time of their founding (at that time, most professional basketball players were white).  In the 1930s and 1940s, they were one of the best basketball teams in the country, along with the New York Rens, another African-American basketball team.  By the 1950s, a lot of black players started playing in the NBA, and the Globetrobbers became a clown team.