Because he wanted to stop the injusticeness. So, he made this speech to express his feeling about how white people and black people must be comparable. And, he also wanted to stop the white people from making and interacting with the black people as they are slaves. In the end, his dream became true. The injustice stopped, the slavery stopped, and finally, the black and white people became equal.
On August 28, 1963, Martin Luther King Jr., delivered a speech to a massive group of civil rights marchers gathered around the Lincoln Memorial in Washington DC.
