Dr. Martin Luther King, Jr. was assassinated 45 years ago today at a motel in Memphis, Tennessee. The civil rights leader was in the southern city to support an ongoing strike by the city’s sanitation workers. King was only 39 years old when he died.

King was born in Atlanta in 1929 and attended a seminary in Pennsylvania before becoming a pastor in Montgomery, Alabama at age 25. He went on to lead the 1955 Montgomery Bus Boycott and founded the Southern Christian Leadership Conference. Throughout his career he organized nonviolent protests throughout the south and helped to organize the 1963 March on Washington. King was awarded the Nobel Peace Prize in 1964.

The day before his death, King delivered his “I’ve Been to the Mountaintop” speech, which contained references to the threats of violence that he routinely received.

While mourning the news that beloved film critic Roger Ebert has died, Twitter users are also remembering the assassination of King and conveying which message of King’s meant the most to them:

[Author’s Note: Cory Booker is the current mayor of Newark, New Jersey]

[Author’s note: Nicolas Maduro is currently the interim president of Venezuela.]