There is slightly more to the story as well. Claudette Colvin had done the stunt before Rosa Parks. However the situation did not look good for the movement as she became part of a scandal considering her age and that she got pregnant resulting from an affair with a married man… and apparently local leaders did not like her demeanor and appearance. So her role had been swept under the rug and Rosa Parks went out and did the same with the backing of the local black leaders.
Not bringing it up to diminish Rosa Park’s contribution, but to bring to attention of Claudette
Here’s her wiki 
