One of the most iconic figures in the American Civil Rights movement, Martin Luther King Jr., remains an essential piece of American history and the progression of black rights across the United States. Captured here by noted photojournalist Marion S. Trikosko in 1964 during a press conference, this remains one of the enduring images of the preacher four years prior to his assassination at the Lorraine Motel in Memphis, TN. King's role in the Civil Rights movement cannot be understated, and he has become nearly synonymous with non-violent protest and peace movements across the globe. This photo was taken only a year after his "I Have a Dream" speech in the March on Washington in 1963, delivered to nearly 250,000 participants in the protest for equal rights. His work in the Civil Rights movement led to the passing of the Civil Rights Act of 1964. The march was one of the largest gatherings of its kind in the United States and was a pivotal turning point in the American Civil Rights movement. It's also considered a key reason for the Voting Rights Act of 1965, another piece of key legislation for the movement. In 1955 King was a leader in the Montgomery Bus Boycott, one of the first protests in the American South. He became the first president of the Southern Christian Leadership Conference (SCLC). King received the Nobel Peace Prize in 1964 for his work in the Civil Rights movement and his belief in nonviolent protest as civil disobedience.