Martin Luther King Jr. was the most prominent civil rights leader during the 1960s. He played a pivotal role in advocating for nonviolent protest against racial segregation and injustice in the United States. Promoting the ideals of equality, justice, and peace, King led movements such as the Montgomery Bus Boycott and the March on Washington, where he delivered his iconic "I Have a Dream" speech. His efforts were instrumental in the passage of significant civil rights legislation, including the Civil Rights Act of 1964 and the Voting Rights Act of 1965. King's legacy continues to inspire social justice movements today.