From BR Bullpen

The Pythian Baseball Club of Philadelphia was one of the earliest and best black baseball clubs. It consisted of four teams, and played other black clubs after its founding in 1866. It was a social club as well, and consisted of the upper crust of black society in Philadelphia. For more, see Negro Leagues history.

In 1869, the Pythians beat an all-white team, in the first recorded instance of an all-black team playing an all-white team. The game was an "exhibition" game, since the Pythians had not been allowed into either the state or national associations of white clubs.