Settings are very important to most texts given it allows the reader to make certain inferences about the characters simply based upon where the story takes place. Any actions which conflict with the setting may cause conflict for the reader.
That said, the setting of Langston Hughes' play Mulatto: A Play of the Deep South is of the utmost importance. The fact that the play takes place in the South, during a period of slavery, allows readers of the play to infer that prejudice and oppression will be main themes seen in the play.
The fact that Thomas Norwood, a Georgia plantation owner, has mulatto children (half black and half white--given his sexual relationship with his maid Cora) allows readers to understand the greater problems Norwood faces in the eyes of the community. Mulatto children, although part white, were simply not accepted as being white at all.
That said, the prejudices of the South were even more harsh against mulattoes. Norwood's son, Robert (or Bert as Cora calls him) believes that he should have the rights of whites. His pushing of this causes much conflict for Norwood.
Symbolically, the door of Norwood's home is very important. It represents the barrier between the prejudice world outside and the semi-prejudice world within. Norwood is greatly conflicted about being a father to his mulatto children and being a white landowner with slaves.
Overall, the setting of the play impacts Norwood. Given that certain behaviors were expected of both whites and blacks during periods of slavery (especially in the South), the conflict which Norwood faces (both internally and externally) mirror the conflict erupting in the United States.
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