Why do the Baltimore Orioles wear black on Fridays?

Answer 1

On September 6, the Orioles celebrated the 75th anniversary of the Baltimore Black Sox' 1932 season. That year, the Sox were credited with a championship but never received the proper recognition since their league folded midseason. Current Orioles players and coaches wore 1932 Baltimore Black Sox replica uniforms during the game. The black sox was a negro league team.

Answer 2

The orioles only wear black on Friday at home because this is their alternate uniform.