THIS PULITZER PRIZE WINNING BOOK was accused of being lifted from Harold Courlander's "The Africans." Since there was an out of court settlement, it didn't matter in the end since the wildly popular mini-series paid for it all.
Roots (yes I just realized the book is being accused) (edited at 5:28 pm, March 17, 2017 (CDT))
Original Answer: Roots