Since baseball’s beginnings in the 1860s, many of its greats have been African American. But for years, the sport was segregated. Black athletes couldn’t compete on teams in the white-controlled major leagues. Instead, they played in the Negro leagues­. (The term Negro, once commonly used to refer to black people, is now considered outdated and offensive.)

The first of these leagues, the Negro National League, was founded 100 years ago by eight black team owners. Other such leagues followed. They produced legendary teams including the Homestead Grays, which featured future baseball Hall-of-Famers Josh Gibson and Buck Leonard (above, second and third from left).

Yet when this photo was taken, in 1946, that world was about to change. The next year, Jackie Robinson became the first black man to integrate the major leagues. The best African American players eventually joined him. By the early 1960s, the Negro leagues were history.