Walker was born on October 7, 1856, in Mount Pleasant, Ohio (per the Society for American Baseball Research). His first go at the game, playing catcher, was at Oberlin College in 1877. In between his studies he played for minor leagues, then transferred to the University of Michigan, where he continued to showcase his standout talent. In 1883, he left his studies behind to focus on baseball and was signed in Toledo. That same year the team entered the then-professional league — American Association.

Racial discrimination prevented him from fully playing. However, on May 1, 1884, Walker would get his chance to debut with his team in a major league game against the Louisville Eclipse. That day he made history and was the first African American baseball player to play in a professional game. It was short-lived, however, as Walker ended up going to play in minor leagues before leaving the game for good.

As historic as both Robinson and Walker’s debuts were, they still weren’t exactly the “first.” The very first Black man to play in any major league baseball game in America was William Edward White. He played for the Providence Grays, who were part of the then-National League. But he only played one professional game, on June 21, 1879 (via Society for American Baseball Research). Walker played for a full season (per Baseball Stats) but also endured racism and discrimination in order to participate in the sport. Walker’s single year in the big leagues is what he is still remembered by.