Trivia: The "lift voice" heard during the theme song in each episode is that of Stephanie Gathercole, who played Mr. Rumbold's secretary in the earliest episodes.
Trivia: Frank Thornton, Mollie Sugden, John Inman, Wendy Richard and Nicholas Smith are the only actors to appear in all 69 episodes of the show.
Answer: In minstrel shows there was also a stereotype of black men preying on white women, so that's probably why she was not in black face. Also, Mrs. Slocombe is in blackface because she is an older, stout woman and she fits the "mammy" stereotype.