The specific diversity of the cast was a deliberate choice by Roddenberry, and it was at the time unusual for American network television. Nichelle Nichols as Lieutenant Uhura was a Black woman in a primary command role on a network drama — not a supporting character, not comic relief, but a bridge officer with authority and professional competence. George Takei as Hikaru Sulu was a Japanese-American in a similarly prominent role, three years after the last survivors of Japanese internment camps had returned to their communities. Walter Koenig as Pavel Chekov was a Russian officer — this in 1967, at the height of the Cold War.
The casting of Nichols has a specific historical footnote. She initially considered leaving the show after the first season, feeling that the role was not providing her with enough material. Martin Luther King Jr., whom she encountered at a fundraising event, personally encouraged her to stay — telling her that *Star Trek* was the only show he allowed his children to watch, that her presence on the bridge of the Enterprise demonstrated to Black Americans that they had a future in space and in authority roles, and that leaving would be a mistake. She stayed.
This interaction — between the most visible civil rights leader in America and an actress on a science fiction television show — illustrates something important about what *Star Trek* was doing culturally in 1966 and 1967. It was not simply entertainment. It was a proposition: that the future could be different from the present, that the racial and cultural divisions of mid-1960s America were not permanent, that human beings of all backgrounds could work together as equals toward something larger than any of their individual origins.