Complex sentence: The slaves depicted in "Gone with the Wind" are primarily loyal house servants, such as Mammy, Pork, Prissy, and Uncle Peter, and these slaves are the highest "caste" in Mitchell's caste system of the slaves.
Split into simpler sentences: The slaves depicted in "Gone with the Wind" are primarily loyal house servants, such as Mammy, Pork, Prissy, and Uncle Peter. House servants are the highest "caste" in Mitchell's caste system of the slaves.