(Rachel Orr/The Washington Post; iStock)

In thousands and thousands of unmarked cemeteries throughout the South, the gradual decay of human remains forms shallow depressions in the earth. There is no comprehensive list of such sites, and many have been destroyed. Still, in places such as Charlotte and Orange and Bedford and Hendersonville and Tuscaloosa, the ground undulates over those believed to have been slaves.

There are places in the political landscape, too, where the ground shifts ever so slightly, where slavery has warped the electoral terrain.

In the South, it seems, old prejudices have persisted. Southern counties that had more slaves on the eve of the Civil War are distinct from their neighbors: White residents in those areas are more hostile toward African Americans and they are more likely to vote Republican today, new research shows. Drawing on archival Census figures and recent polls, the study adds to an expanding body of evidence on the importance of racial anxiety to the predominantly white Republican coalition.

"The underlying racial hostility goes on in the culture, passed on from generation to generation," said David Sears, a psychologist at the University of California, Los Angeles. "Local culture doesn't change very quickly."

Of course, many things have changed in the South in the century and a half since emancipation. Slavery's lingering political effects are often buried in the data, just as many old graves have been paved over and others are hidden by weeds and brambles.

If you know what to look for, though, you can still see the depressions.

Slavery's crescent

Before the Civil War, the Southern landowners who most relied on slaves lived in a crescent that extended south and west from South Carolina, following the Piedmont through Georgia and Alabama, and then north along the Mississippi River.

This was where Southerners farmed cotton on plantations, between the coast and the rugged terrain of the Appalachians. The crop demanded so much manpower that it would not have been profitable without slavery, said Harvard University's Maya Sen, one of the authors of the study. About 4 million people, or 32 percent of the population, were enslaved in the South in 1860.

Sen and her collaborators, Stanford University's Avidit Acharya and Harvard's Matt Blackwell, argue that slavery and the systems of repression that replaced it after the Civil War continued to shape how white Southerners thought about race for generations to come.


 

Following emancipation, not only did white Southerners lose the source of their economic power in this region. Given their numbers, the former slaves also threatened to end white political dominance at the polls.

In response, white Southerners in those counties with large black populations found ways of preserving their power over the freed slaves. Soon after the war, for example, former planters developed the system of sharecropping, which allowed them to maintain their control over black labor. It was an improvement over slavery, but it was still a form of peonage. Former slaves, eager to farm for themselves, borrowed their capital from white merchants at usurious rates.  Tenants had to give up much of their crop to their creditors and landlords.

Elsewhere in the South, prejudices waned more quickly after the fall of the Confederacy. According to the study, where relatively few former slaves lived, white Southerners had less need for such practices.

In the 20th century, when white Southerners developed new legal and extralegal methods of oppression. The end of Reconstruction allowed white, Democratic governments to disenfranchise black voters and to segregate public spaces. These governments also acquiesced in thousands of lynchings.

Acharya, Blackwell and Sen found that in two otherwise similar counties, a slight difference of 10 percentage points in the enslaved population in 1860 was associated with 1.89 additional lynchings per 100,000 residents in the years between 1882 and 1930. Previous research has shown that lynchings were more frequent when the price of cotton fell, evidence that white Southerners attacked black victims when their economic dominance was threatened.

'It is definitely there'

Today, most of the old plantations have been sold off. Where slaves once picked cotton, there are subdivisions and stadiums. The prejudice, however, remains.

"There are still a lot of people who think blacks are simply inferior to whites," said Roger Ransom, an economic historian at the University of California, Riverside. "It is definitely there, and I don’t think it ever went away."

Acharya, Blackwell and Sen examined data on racial attitudes from national polls conducted in 2010 and 2011, using the responses of white participants in the states of the former Confederacy, including West Virginia, as well as Missouri and Kentucky, slave states that did not secede. Those in counties where more slaves lived in 1860 were more likely to hold negative views of African Americans.

For example, they were more likely to disagree with the statement, "Generations of slavery and discrimination have created conditions that make it difficult for Blacks to work their way out of the lower class." They were less likely to support affirmative action. There were many respondents who held similar views living in other counties, too, but the differences were clear when the researchers looked at the results for all of the tens of thousands of Southerners who participated in the polls.

'The party of Lincoln'

Those white Southerners who live where cotton was king are also substantially less likely to identify as Democrats today. Among otherwise similar counties, a difference of 20 percentage points in the enslaved population in 1860 was correlated with a difference of 2.3 percentage points in the share of white Democrats.

Recent research by economists Ilyana Kuziemko and Ebonya Washington suggests that white Southerners who defected from the Democratic party after the civil-rights movement were those with the most conservative views on race. Democrats who held moderate and conservative views on other issues and who lived in other parts of the country largely remained loyal.


 

Polls consistently show that Republicans are more likely to hold racial prejudices, and not just in the South. Nationally, almost one in five Republicans opposes interracial dating, compared to just one in 20 Democrats, according to the Pew Research Center. While 79 percent of Republicans agree with negative statements about blacks such as the one about slavery and discrimination, just 32 percent of Democrats do, the Associated Press has found.

Conservative leaders argue that Republicans do not exploit racial anxiety to win votes, and that any differences between Republicans and Democrats are coincidental. It could be, for example, that a platform of limited government is naturally more appealing to people who live in sparsely populated areas where independence and autonomy are valued, and that people who live there also hold more intense biases for historical reasons.

"This party does not prey on people’s prejudices. We appeal to their highest ideals," Rep. Paul Ryan (R-Wis.), the speaker of the House, told reporters Tuesday. "This is the party of Lincoln."

Speaking as voters in 13 states cast their ballots on Super Tuesday, House Speaker Paul Ryan said potential Republican presidential nominees must reject any group "built on bigotry." (Reuters)

Prejudices and ideals

Other research, however, suggests that the party does benefit from racial antipathy.

Sears of the University of California has found that even among white voters with equally conservative views on issues unrelated to race, those with more negative views about African Americans are more likely to vote Republican. He and Michael Tesler, a political scientist at the University of California, Irvine, showed that there were many racially conservative white voters who supported John Kerry and President Clinton when they were candidates, but who voted against President Obama.

"The conservatives say, 'Well, we just like small government down here.' Well, why? Why is that?" Sears asked.

Sears said that white Republicans have a wide range of reasons for supporting their candidates, and that the "ideals" Ryan mentioned are deeply important to many such voters.

At the same time, Sears suggested that GOP doctrine on the importance of personal responsibility, together with elevated rates of black poverty and unemployment, help some Republicans rationalize their belief that people of color are inferior -- beliefs they probably developed in childhood.

In general, there is evidence that children receive their racial prejudices from their parents, as well as the other adults in the communities in which they live. The three political scientists examined data from a national survey of high school seniors first conducted in 1965, which found that the students' feelings about race were closely correlated with those of their parents.

Those statistics didn't change at all in 1997, when surveyors talked to the former students again. In other words, adults' feelings about race were still influenced by how they grew up after their 50th birthdays, even during a period when attitudes toward race in society at large were liberalizing rapidly.

"I grow up with this kind of negative feeling toward blacks, maybe disgust or repulsion," Sears said. "The culture gives me the reasons why I feel that way, provides the justifications."

Blackwell, one of the authors, agreed. "People in general tend to think of their views as their own, conclusions that they came to after thinking long and hard about the facts," he said. "There's sufficient evidence out there to show that's not the way people have come to form beliefs about the world and about politics, in general."

The new study does not provide direct evidence that those white Southerners are more likely to vote Republican because Republican politicians appeal to their racial anxieties. Rather, it suggests that racial biases along with political beliefs are transmitted from one generation to another as part of the overall culture of a particular place.

"If you think back to that culture, the role of slavery, the role of racial hierarchy, the role of racial hostility was so powerfully embedded," Sears said.

Slavery's legacy

Recently, researchers working around the world have been discovering that a society's fears, anxieties and hatreds have remarkable longevity.

In Africa, the descendants of those tribes who suffered most under the slave trade are more likely to be mistrustful today. In Germany, the Nazi Party won a larger share of the vote in cities where Christians had blamed Jews for the Black Death and massacred them six centuries earlier, researchers found.

Together, these results suggests that societies can be scarred and traumatized, like people. For psychologists, political scientists and pundits who hope to understand why voters do what they do, these findings argue for paying a little more attention to history.

After all, slavery's enduring legacy is evident not only in statistics on black poverty and education. The institution continues to influence how white Southerners think and feel about race -- and how they vote. Slavery still divides the American people.

"When we study public opinion, we tend to focus on the now," Sen said. "These political attitudes really can persist over generations, and last an incredibly long time."

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