If you'd like to put Malcolm X's work into a historical context, you will want to know something about the Civil Rights Movement in the U.S. To get you started, here's a good general introduction to segregation and Jim Crow from The Columbia Encyclopedia, as well as some related links.
CNN.com's historical timeline on the Nation of Islam starts in 1930 and continues to the present.
As you probably know, Malcolm X changed his name because he considered the name his parents gave him to be a slave name. To put this issue into a historical context, consult this chronology of U.S. statutes concerning slavery.