In November 1860, Thomas R.R. Cobb, author of an influential legal defense of slavery, called for the immediate and unconditional secession of Georgia. Cobb would go on to serve in the Confederate Congress and later became a general for the Confederacy. He was killed in 1862 during the Battle of Fredericksburg.

Fifty years ago this summer, Cobb’s great-grandson, Charles L. Weltner, issued another decisive call on an equally pressing issue in the South: the 1964 civil rights bill. Weltner’s words would echo through the red hills of Georgia and beyond.

Weltner, a first-term congressman from Georgia’s Fifth District, decided to buck his state’s leadership including U.S. Sens. Richard B. Russell and Herman E. Talmadge, depart from the South’s entrenched racial tradition and make history on the defining issue of the era.

“We must not remain forever bound to another lost cause,” Weltner said before becoming the sole representative from the Deep South to vote for the landmark 1964 Civil Rights Act.

Weltner had defeated segregationist James C. Davis, a 16-year incumbent, for the seat in 1962. But the moderate freshman voted against the civil rights bill in June 1963 and again the following February, both times over concerns about Title II, the controversial public accommodations section.

The bill came back to the House for a final vote in July 2, 1964. “What … is the proper course?” a wavering Weltner asked on the House floor. “Is it to vote ‘no,’ with tradition, safety — and futility?”

Although Weltner was far from a civil-rights advocate, the growing strength of the civil rights movement forced him to reconcile his Southern heritage with the stain of escalating racial violence. Weltner was particularly outraged by the Birmingham church bombing, which he categorically condemned in September 1963 — a speech that helped burnish his image as a Southern moderate.

As had happened with many other Southerners, civil rights victories across the South had challenged Weltner’s racial views. “My career was not the issue. My future was not the question,” Weltner recalled years after the vote. “There was a greater issue, a larger question, a higher cause. Indeed, at stake was the highest cause in the affairs of men: the cause of simple justice for every American.”

Weltner also recognized that a vote against the final passage of the bill would be a vote to stifle progress in the South. It would be a victory for the forces that had blocked social, economic and political development in the decades since his great-grandfather had fallen at Fredericksburg.

“I would urge that we at home now move on to the unfinished task of building a New South,” Weltner said in his speech on the House floor. The New York Times reported that “applause burst from the civil rights advocates on both sides of the aisle as Mr. Weltner finished. His fellow Southerners sat stunned.”

Before the final vote, Carl Vinson, a Georgia congressional veteran of 50 years and dean of the House, approached Weltner with a thinly veiled warning. “Well, profiles in courage, and all that. But I hate to see you throw away a promising career,” Vinson told his junior colleague.

Vinson’s words were prophetic. Weltner won a second term in November 1964, riding strong black support and boosting hope for a lasting Democratic biracial coalition in the district and, possibly, the state. But that vision proved ephemeral.

A month prior to the 1966 congressional election, Weltner stunned the nation by announcing he would withdraw from the race. Rather than take an oath of loyalty to the Democratic Party ticket headed by Lester G. Maddox, the party’s arch-segregationist gubernatorial nominee, Weltner would leave Congress. “I will give up my office before I give up my principles,” Weltner said. “I cannot compromise with hate. I cannot vote for Lester Maddox.”

In an era of intense partisanship and gridlock in Washington, it serves us well to recall a politician who — in the unlikeliest moment — cast historical sentiment, regional attachment and generational ties aside and voted with his conscience.

Weltner, like his secessionist great-grandfather before him, had crossed the Rubicon. “The unfinished task of building a New South” would finally begin.

Nathaniel Meyersohn is a senior at Emory University. He is currently writing an undergraduate honors thesis on Charles L. Weltner and the New South.