April 4: 1968 : Dr. King is assassinated

From our Friends at the History Channel

Just after 6 p.m. on April 4, 1968, Martin Luther King Jr. is fatally
shot while standing on the balcony outside his second-story room at
the Lorraine Motel in Memphis, Tennessee. The civil rights leader was
in Memphis to support a sanitation workers' strike and was on his way
to dinner when a bullet struck him in the jaw and severed his spinal
cord. King was pronounced dead after his arrival at a Memphis
hospital. He was 39 years old.

In the months before his assassination, Martin Luther King became
increasingly concerned with the problem of economic inequality in
America. He organized a Poor People's Campaign to focus on the issue,
including an interracial poor people's march on Washington, and in
March 1968 traveled to Memphis in support of poorly treated
African-American sanitation workers. On March 28, a workers' protest
march led by King ended in violence and the death of an
African-American teenager. King left the city but vowed to return in
early April to lead another demonstration.

On April 3, back in Memphis, King gave his last sermon, saying, "We've
got some difficult days ahead. But it really doesn't matter with me
now, because I've been to the mountaintop...And He's allowed me to go
up to the mountain. And I've looked over, and I've seen the Promised
Land. I may not get there with you. But I want you to know tonight
that we, as a people, will get to the promised land."
Read the rest of the story and see the video at the History Channel

To read more about Civil Rights here are couple more links
Timeline of the African-American Civil Rights Movement
Freedom Riders website chronology, extremely detailed