Lewis received the Presidential Medal of Freedom in 2011

John Lewis became involved in the Civil Rights movement at 15 years old.

"I heard the words of Martin Luther King Jr. on our radio and I heard about Rosa Parks" he said in 2014. "It seemed like Martin Luther King Jr. was speaking directly to me, saying John Lewis, you too can do something. You can make a contribution."

He began organizing sit-ins at segregated lunch counters in the Nashville area in college while studying at Fisk University.

Lewis then participated in the Freedom Rides in 1961, protesting segregation at interstate bus terminals by sitting in seats reserved for white customers.

At 25, Lewis marched with King from Selma to Montgomery, and was on the Edmund Pettus Bridge on Bloody Sunday, where he was beaten by police and knocked unconscious.

"I gave a little blood on that bridge," he said. "I thought I was going to die. I thought I saw death."

Fifty years later, at an event to commemorate the incident, he spoke before President Barack Obama on the bridge, just feet away from where he was nearly killed.

"We must use this moment to recommit ourselves to do all we can to finish the work -- there's still work left to be done," he said.