Jackie Robinson broke boundaries as the first African American player in Major League Baseball. But long before Jackie changed the world in a Dodger uniform, he did it in an army uniform.

As a soldier during World War II, Jackie experienced segregation on a daily basis—separate places for black soldiers to sit, to eat, and to live. When the army outlawed segregation on military posts and buses, things were supposed to change.

So when Jackie was ordered by a white bus driver to move to the back of a military bus, he refused. Instead of defending Jackie’s rights, the military police took him to trial in a court-martial. But Jackie would stand up for what was right, even when it was difficult to do.