Fifty-five years ago, the late Rosa Parks refused to give up her seat for a white person. She was subsequently arrested and put in Jail. Google have remembered this day with a Google Doodle illustration. This is not on the Google UK version but on Google USA.
As a result the Montgomery, Alabama bus boycott took place and lasted for about 381 days. This one act alone pushed the Civil Rights Movement into full force.
For more information please have a look at Rosa Parks website