One hundred and fifty years ago, on January 14, 1868, an extraordinary convention opened in Charleston, South Carolina, the cradle of the Confederacy.

That afternoon, a biracial group of men—most of whom were black and some of whom had recently been enslaved—gathered at the elegant Charleston Club House, which had only recently been the refuge of city elite. They came to redraft South Carolina’s uniquely undemocratic constitution. One of nearly a dozen interracial meetings held in the former Confederacy between late 1867 and 1869, the South Carolina Constitutional Convention was part of a larger Reconstruction-era campaign to rebuild the nation in a more just fashion.

Today, the South is primarily associated with hidebound conservatism. But for a few brief years after the Civil War, this campaign transformed the region into the most progressive place in America—providing a blueprint for a liberal resurgence that may already be under way in the 21st century South.

The antebellum South had long been a conservative bastion, characterized by its dogged commitment to states’ rights, low taxes, strict construction of the Constitution, and especially the maintenance of traditional gender roles and white supremacy. Fearful that Abraham Lincoln’s presidential election threatened slavery, white South Carolinians in late 1860 had gathered just a few blocks from the Charleston Club House to secede from the United States, sparking four bloody years of civil war.

Less than a decade later, however, former slaves and freeborn blacks helped choose delegates to state constitutional conventions across the South, including the one in Charleston. These groundbreaking 1867 and 1868 elections, which followed a congressional mandate, gave birth to real, if short-lived, interracial democracy. African Americans occupied one-quarter of the seats in the conventions as a whole and a majority of them in Louisiana and South Carolina.

The conventions drafted constitutions reflecting the progressive priorities of their mostly Republican delegates, whose party represented the left wing of American politics, particularly on race. Whereas postbellum Democrats campaigned on racist platforms, most Republicans were committed to using government to secure black rights.

All of the new constitutions guaranteed black men the right to vote, a feature that for a time reshaped the American body politic. As late as 1866, less than 1 percent of African American men in the United States had been eligible to vote, and not one of them lived south of the Mason-Dixon Line. Up north and out west, white citizens had shown little interest in expanding voting rights, rejecting colorblind suffrage initiatives in Connecticut, Ohio, and Kansas in 1867. Yet by the following year, hundreds of thousands of black men were voting in national, state, and local elections held in the seven ex-Confederate states that had by then ratified their constitutions—all before the 15th Amendment enfranchised black men throughout the country in 1870.

The Reconstruction constitutions also protected black civil rights, unlike those of most Northern states. They outlawed inhumane and undemocratic provisions from the antebellum era, including corporal punishment for crime and property-owning qualifications for jury service. The conventions in Georgia and the Carolinas expanded the property rights of married women, black and white.

No convention was as revolutionary as South Carolina’s, if only because no state had so reactionary a political culture or so outdated a constitution. Christened the “Congo Convention” by opponents, the black-majority assembly abolished debtors’ prison and property-owning qualifications for serving in the state legislature. It provided for the popular election of the governor and the state’s presidential electors. And delegates also paved the way for the legalization of divorce for the first time in South Carolina history.

By enfranchising black men, the new state constitutions laid the groundwork for Republicans to assume power throughout the South by the early 1870s. African Americans made up a majority of the electorate in three Southern states and a sizeable proportion in the rest. Aided by the Union League, a grassroots coalition of Republican clubs that promoted voter registration, black turnout often approached 90 percent during Reconstruction.

Just as remarkable was the composition of the body of elected officials in the Reconstructed South. African American voters joined with a smaller contingent of Northern transplants and native-born whites—dubbed “carpetbaggers” and “scalawags,” respectively, by detractors—to elect a wave of Republicans, many of whom were black. At a time when black office-holding was almost unheard of elsewhere, hundreds of African American men in the South held positions ranging from sheriff and county magistrate to state supreme court justice and U.S. senator. Black political power was strongest in South Carolina, where African American legislators controlled the lower house of the General Assembly from 1868 through 1876.

The biracial Republican-led legislatures were not just progressive in their makeup—they also implemented a broadly progressive agenda that put them at the vanguard of activist government in America. They outlawed racial discrimination in theaters, hotels, and restaurants. They instituted public welfare and relief programs, building hospitals and orphanages and establishing boards of health. Some Southern cities provided firewood and food to the poor. Perhaps the most significant accomplishment was the wholesale creation of public-school systems that were open to every child, regardless of race.

These Republican governments were far from perfect. None enacted the widespread land redistribution that Southern freedpeople demanded and deserved as compensation for centuries of slavery, and several legislatures were plagued by corruption (though no more so than those controlled by the North’s Democratic political machines).

But the biggest problem Republican regimes faced was Southern conservatives’ refusal to abide the very interracial democracy that they represented—a resistance that ultimately led to the overthrow of that democracy and decades of whites-only rule. By 1877, Democrats and their terrorist allies, most notably the Ku Klux Klan, had used intimidation and violence to drive Republicans from office across the former Confederacy.

Returned to power, white conservatives soon scrapped Reconstruction-era reforms in favor of limited government and second-class citizenship for African Americans. Drafting new laws and constitutions that disenfranchised blacks, these Democrats instituted a political monopoly known as the “Solid South.” This stranglehold lasted into the 1960s, when the civil-rights movement—sometimes referred to as the “Second Reconstruction”—shattered the Jim Crow regime with support from the national Democratic Party. The national party’s progressivism led Southern conservatives to bolt to the GOP, which by then had assumed the mantle of small government and states’ rights and increasingly appealed to white resentment over desegregation.

By the end of the 20th century, the term “Solid South” had been redefined, with the Republican Party—conservatism’s new standard-bearer—holding sway across the region. As of 2011, Republicans controlled 81 percent of statewide offices in the South. In the 2016 presidential election, every Southern state but Virginia backed Donald Trump, suggesting that conservatism’s tenacious grip on the region would not soon relent.

Yet the long view of Southern political history points to another possibility. Reconstruction shows that progressive politics can thrive in even the most seemingly inhospitable of places and times. Conditions in the South today, in fact, are not entirely unfavorable for a liberal revival. Democrats in some Southern states have demographics on their side, not unlike Republicans in the black-majority states of the 1860s and 1870s. Trump’s margin of victory in Texas was 800,000 votes, but 4 million eligible voters of color in the state did not cast ballots, including 3 million Latinos, a reliably Democratic constituency. In Florida, an influx of Puerto Ricans displaced by Hurricane Maria is accelerating the state’s shift toward the Democratic column.

Southern progressives are also beginning to demonstrate that they can get their supporters to the polls, just as the Union League did with Republican voters in the late 1860s. Despite Alabama’s 2011 voter-identification law, which had reduced turnout in the state’s most diverse counties, this past fall an army of grassroots organizers targeting black voters helped elect Democrat Doug Jones to the U.S. Senate over Republican Roy Moore. African Americans also put Democrats over the top in Virginia, where the party recently retained the governor’s mansion and gained 15 House of Delegates seats. And the number of progressive whites is growing: College-educated Southern white suburbanites are abandoning the GOP, and white migrants to the South—latter-day carpetbaggers, a surging population—are more likely to vote Democratic than Republican.

Skeptics may see recent electoral gains solely as a reaction to Trump’s deeply unpopular presidency or, in the case of Alabama, ascribe them to the fact that Moore was a singularly compromised candidate. But this perspective overlooks developments that predate the most recent elections. Beginning in 2013, the Moral Monday movement galvanized thousands of progressives in North Carolina to push back against the Republican-controlled legislature, replace the state’s Republican governor with a Democrat, and help launch similar movements in other Southern states.

Moreover, Southern cities have been Democratic strongholds for decades. By 2015, 22 of the mayors in the region’s 30 largest cities were Democrats. In the face of opposition from Republican state governments, interracial coalitions in these urban areas have advocated for minimum-wage increases, LGBT nondiscrimination ordinances, and the removal of Confederate monuments.

Can left-leaning Southerners prevail in the long run against conservative legislatures intent on blocking municipal-level reform and curbing voting rights? With a federal government hostile to its aims, can a larger progressive coalition win on the strength of grassroots activism alone?

The challenges to doing so today are real, but a century-and-a-half ago, they were far more formidable. Progressive Southerners in 2018 are not, as their forebears were in the 1860s, battling a ruling class that had run the South like a fiefdom for centuries. They are not working to transform a region defined by its dedication to keeping 4 million African Americans in chains, a region whose sons had fought and died for that cause. They are not building a new society largely from scratch.

How many Americans—north or south, black or white—would have predicted in 1861, when the Civil War began, or even in 1865, when it ended, that the South would become a hotbed of progressive politics in just a few short years? Likely very few.

William Barber II, leader of North Carolina’s Moral Monday movement, argues that present-day activists should see themselves as the heirs of that revolutionary political experiment. “I believe the turmoil we are witnessing around us today,” Barber has written, “is in fact the birth pangs of a Third Reconstruction.”