If you want to understand Donald Trump, you have to understand the politics of the Jim Crow South. Though Trump’s brand of racist populism breaks from the views expressed by elites in both political parties today, it has deep roots in the United States — and those roots are anchored firmly in one of the most reviled eras in our nation’s history.

For a century following the Civil War, the American South was largely a collection of one-party states, as white supremacists rallied behind the political party that wasn’t the party Abraham Lincoln. Yet, while white Democratic politics were almost universally racist during the Jim Crow era, this unity on the issue of race obscured very deep divides on fiscal policy. While down-the-line conservatives like Virginia Sen. Harry Byrd were a force in Southern politics, they stood in contrast to a more bipolar kind of politician who was simultaneously cruel — often to the point of outright murder — towards African Americans, while also using the levers of government to benefit poor whites.

Donald Trump is the heir to this second breed of politician.  ...

Benjamin Ryan Tillman grew up in the shadow of what passed for a feminist success story in the antebellum South. After Tillman’s father died, his mother took over her late husband’s plantation, nearly doubled the size of the family farm and eventually became one of the wealthiest slaveholders in her county. She would also, as I explain in my book, Injustices: The Supreme Court’s History of Comforting the Comfortable and Afflicting the Afflicted, raise one of the most powerful defenders of white supremacy in the nation. Probably more than anyone else in South Carolina’s history, “Pitchfork Ben” Tillman, as he was known during his political career, laid the legal groundwork for Jim Crow in his state — often advancing his racist views through murderous tactics. 

Tillman never fought in the Confederate army. Though he volunteered, he was kept from the battlefield by an infection that cost him his left eye. More than a decade later, however, the future governor and senator took up arms in a similar effort to shackle African Americans through violence. 

After a standoff between white farmers accused of forcing their way through a black militia parade at gunpoint, and the militiamen who were accused of leveling bayonets at the farmers, Tillman joined a white supremacist “rifle club” in providing armed support for the farmers. Tillman’s rifle club surrounded the black militiamen and eventually took them prisoner during a violent exchange in which one man on each side was killed. “It was agreed,” Tillman later said of this exchange of a life for a life, “that we could not have a story like that go out as the record of the night’s work.” So the rifle clubs selected five of their black prisoners to be marched “a little ways down the street and shot.” When one of the executioners ran out of rifle cartridges, Tillman lent the white man his gun.

Shortly after this massacre, the rifle club elected Tillman as their captain. It was one of many elections that he would go on to win. During two terms as governor and nearly four terms as a United States senator, the one-eyed racist became the puppet master behind South Carolina’s Democratic Party, filling ranks with loyal “Tillmanites” who all displayed their loyalty by displaying a silver pitchfork on their lapel.

Throughout his time in office, Tillman touted violent terrorism as a tactic for maintaining white supremacy. In a 1909 speech, Senator Tillman called for “terrorizing the Negroes at the first opportunity by letting them provoke trouble and then having the whites demonstrate their superiority by killing as many of them as was justifiable.” That was more than a decade after he pushed a new constitution through an 1895 convention that disenfranchised black voters.

Yet there was also another side to Tillman. Though he offered South Carolina’s black residents nothing more than violence and oppression, he also promised a far better life to the state’s poor whites. ...