The correct answer to this open question is the following.
We are talking about Hinton Rowan Helper (1829-1909) who was a native of North Carolina who wrote the book "The Impending Crisis of the South. How to meet it." In this book, he commented on the relationship between the north and the south to a degree that the Republican Party seriously considered some of his ideas. Some historians say that his approach helped Abraham Lincoln during his presidential campaign. Of course. his ideas caused controversy in the south where the book was banned in states such as North Carolina. In the book, Helper critiqued slavery and slave owners. He called "criminals." He advocated slavery rebellion and being the case, the use of violence to get the slave's freedom.