What historic event took place during the March on Washington?

The March on Washington for Jobs and Freedom, which occurred on August 28, 1963, is most famously remembered for Martin Luther King Jr.'s "I Have a Dream" speech. This event drew more than 250,000 participants and is considered a pivotal moment in the American civil rights movement. King's speech articulated the aspirations of millions of African Americans and served as a rallying cry for equality and justice. His powerful words highlighted the urgency of civil rights, focusing on the desire for a nation where all individuals would be judged by the content of their character rather than the color of their skin.

While the Civil Rights Act was signed in 1964, the march itself did not involve a signing. The NAACP was founded earlier, in 1909, and its establishment is not connected to the March on Washington. Additionally, the Freedom Riders began their journey in 1961, two years prior to the march, aimed at challenging segregation in interstate bus travel. Thus, the "I Have a Dream" speech stands out as the defining moment of the March on Washington, making it the correct answer.