on July 14, 1887, Cap Anson's Chicago White Stockings(cubs) were scheduled to play the Newark Giants of the International League, which had Walker and George Stovey on its roster. After Anson marched his team onto the field, military style as was his custom, he demanded that the blacks not play. Newark capitulated, and later that same day, league owners voted to refuse future contracts to blacks, citing the "hazards" imposed by such athletes.

 

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i found this kind of interesting

another tid bit

 

In 1944, Bill Veeck tried to buy the Philadelphia Phillies with the intention of signing black ballplayers immediately. When Judge Landis, Baseball Commissioner, commissioner of Major League Baseball, was informed of Veeck's plan, he had the National League buy the team and award it to William Cox.