Joe Biden, who last week blasted President Trump over a protest to bring down a statue of Robert E. Lee, voted to restore the Confederate general's citizenship early in his Senate career.

In 1975, Biden joined a unanimous Senate vote to restore citizenship to Lee, 110 years after the Virginian surrendered his Army of Northern Virginia to the Union general and future President Ulysses S. Grant. There were 10 dissenters in the House of Representatives, among them Rep. John Conyers Jr., a black Democrat from Michigan, who scoffed that the resolution was “Bicentennial fluff." Conyers retired in 2017.

Controversy over Lee was stoked last week when the former vice president, a leading 2020 Democratic presidential candidate, slammed Trump over his remarks after the violent "Unite the Right" rally in Charlottesville, Va., in August 2017 in which white supremacists gathered to denounce plans to take down a Lee statue. After Biden's video, Trump responded that he was referring to supporters of Lee when he said there were "fine people" on both sides.

Biden's 1975 vote came after a discovery in the National Archives that Lee's post-Civil War oath of allegiance, a necessary condition for his citizenship, had never reached President Andrew Johnson. Lee's 1865 request for citizenship was approved by Grant, but it did not include the oath of allegiance to the U.S., which was necessary for a pardon and his citizenship. During the Civil War, the citizenship of Confederates had been revoked.

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Lee swore the oath, which read: "I, Robert E. Lee, of Lexington, Virginia, do solemnly swear, in the presence of Almighty God, that I will henceforth faithfully support, protect and defend the Constitution of the United States and the union of the states thereunder, and that I will, in like manner, abide by and faithfully support all laws and proclamations which have been made during the existing rebellion with reference to the emancipation of slaves, so help me, God."

But the absence of the oath of allegiance, which was not discovered until 1970, meant that when he died in 1870, he was not an American citizen.

In July 1975, Biden was two-and-a-half years into his Senate career, which would last for 36 years, before an additional eight as vice president under President Barack Obama. Voting along with him were segregationists or former segregationists such as Sens. James O. Eastland of Mississippi, Herman Talmadge of Georgia, and Robert Byrd of West Virginia — all Democrats — and Sens. Strom Thurmond of South Carolina and Jesse Helms of North Carolina, both Republicans.

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Biden was a prominent opponent of busing, designed to stop the segregation of schools, and even embraced the concept of segregation in 1975, claiming it was a matter of "black pride." He had recently boasted of his friendships with segregationists.

Debate about Lee's legacy has raged since the Charlottesville rally. Trump told reporters on Friday that Lee was a "great general" as he defended his response to the "Unite the Right" rally, which left activist Heather Heyer dead after a white supremacist, later charged with murder, drove his car into a crowd of counterprotesters.

"If you look at what I said, you will see that question was answered perfectly. And I was talking about people that went because they felt very strongly about the monument to Robert E. Lee, a great general," Trump said. "Whether you like it or not he was one of the great generals. I've spoken to many generals right here at the White House, and many people thought of the generals they think he was maybe their favorite general. People were there protesting the taking down of the monument of Robert E. Lee. Everybody knows that."

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