Martin Luther King Jr. was a prominent civil rights leader in the United States during the mid-20th century. He was a key figure in the American civil rights movement and is best known for his use of nonviolent civil disobedience in the pursuit of civil rights and racial equality.

King was born on January 15, 1929, in Atlanta, Georgia. He became the pastor of the Dexter Avenue Baptist Church in Montgomery, Alabama, where he first became involved in civil rights activism. He led the Montgomery Bus Boycott in 1955, which marked the beginning of a series of nonviolent protests and actions that aimed to end racial segregation and discrimination in the United States.

King was instrumental in the organization of the Southern Christian Leadership Conference (SCLC) in 1957, a group dedicated to advancing civil rights using nonviolent tactics. He led numerous marches, protests, and demonstrations, including the historic March on Washington for Jobs and Freedom in 1963, where he delivered his famous "I Have a Dream" speech.

In 1964, King was awarded the Nobel Peace Prize for his work in advancing civil rights through nonviolent means. He continued to be a leading voice in the civil rights movement until his assassination on April 4, 1968, in Memphis, Tennessee.

Martin Luther King Jr.'s legacy lives on as one of the most significant figures in the fight for racial equality and social justice in American history. His contributions to the civil rights movement laid the groundwork for the progress that has been made in advancing civil rights and promoting equality for all individuals.