Nichelle Nichols was actually disappointed in the way her character was portrayed (she did nothing but sit at her station and answer hailing frequencies) and was going to quit the role, but she was convinced to stay by none other than Martin Luther King Jr[0].
It was one of the first, if not the first, portrayal of a black woman on television in a non-stereotypical, non-subservient role, even if it was just secretarial duty on a spaceship.
* https://en.wikipedia.org/wiki/Mae_Jemison