From the wikipedia for Negro

"Negro" superseded "colored" as the most polite terminology, at a time when "black" was more offensive.[3] This usage was accepted as normal, even by people classified as Negroes, until the later Civil Rights movement in the late 1960s. One well-known example is the identification by Martin Luther King, Jr. of his own race as "Negro" in his famous 1963 speech I Have a Dream.

During the American Civil Rights movement of the 1950s and 1960s, some black American leaders in the United States, notably Malcolm X, objected to the word "Negro" because they associated it with the long history of slavery, segregation, and discrimination that treated African Americans as second class citizens, or worse.[4] (Malcolm X preferred "Black" to "Negro", but also started using the term "Afro-American" after leaving the Nation of Islam.)[5]

Oh my, its almost as if "negro" is the correct term to use for the time and place!