Token Minority Characters

Yesterday in my American Studies class, we briefly discussed the movie Lincoln and the role of  the African Americans. I have not seen the movie yet, but according to my classmates the only dialogue that was spoken by African American actors was in the first few minutes of the movie. I thought it was interesting how the film is about the act which freed the slaves, but the people who are being freed barely have any dialogue.

Although I don't know if the directors of the Lincoln movie were purposefully discriminating, this discussion reminded me of tokenism. Tokenism is the act of hiring one minority worker in order to have the image of being racially diverse. This is very prevalent in the media today. The first example that I thought of is the TV show Glee. The minorities in the cast consist of one black girl, one Latina girl, one disabled boy, and one Asian couple. The rest of the cast is all white. Another example lies in my classmate Lauren's blog post. She talks about diversity in Disney princess movies. I think it is no coincidence that the movies starring minority characters are the more recent ones.

This poses the question: why do directors and film makers cast the people they do for their
characters? Also, why are certain characters created? Was Mercedes' role on Glee or the rumored Latina princess (as read from Lauren's blog) created to add stories to the plot, or just simply to attempt to show people that the program is inclusive for all groups?