On August 16, 1867, a young farmer named Alfred McDonald Sargent Johnson walked into the courthouse of Cherokee County, Georgia. He had an oath to swear.

The effects of the Civil War were still visible in Canton, a village of about 200 people and the county seat. For one thing, that makeshift courthouse was inside a Presbyterian church—its predecessor having been torched by William Tecumseh Sherman’s men shortly before their march to the sea. For another, Georgia was still under military rule as federal officials debated how best to reconstruct the former Confederate states. How does a government reintegrate the men who, not that long ago, were engaged in a treasonous rebellion?

[Read: Elon Musk’s anti-semitc apartheid-loving grandfather]

Johnson had, like many of his neighbors, taken up arms against the United States. At age 21, he’d joined Company F of the 3rd Georgia Cavalry. The Third had fought in the Chickamauga and Chattanooga campaigns, and Johnson had even been captured as a Union prisoner at New Haven, Kentucky. But he was just a foot soldier in a much larger war. Johnson had not grown up in a stereotypical plantation “big house”; his family’s farm was modest in size and census records do not list him or his father as having owned slaves. He ended the conflict as a private, just as he’d entered it. Johnson might not even have cared much for his war experience; Confederate records list him as having gone AWOL for a period in 1863.

Still, the federal government had decided that even men like him could not return to political power without making at least a gesture of reconciliation. A few months earlier, Congress had passed, over President Andrew Johnson’s veto, an act that required the men of Georgia and other southern states to swear an oath in order to regain their voting privileges. That oath was why Alfred M. S. Johnson was in the courthouse that August day.

There had been much debate in the North, during the war and after it, about how to reintegrate former Confederates into political life—and how forgiving to be of their rebellion. The most radical Republicans wanted to require an “Ironclad Oath” swearing that the prospective voter had “never voluntarily borne arms against the United States” nor given “aid, countenance, counsel, or encouragement” to the Confederacy. Such language would have disenfranchised most white southern men.

The Wade-Davis Bill of 1864 would have required a majority of white men in each state to take the Ironclad Oath before full readmission to the union. Lincoln pocket-vetoed that bill, considering it too harsh. He’d backed a much more lenient plan requiring only 10 percent of a state’s pre-war voters to swear an oath before that state could be readmitted. And his version was more forgiving than the Ironclad Oath, requiring only future loyalty—that they would “henceforth faithfully support, protect, and defend the Constitution of the United States and the Union of the States thereunder.”

The oath Alfred Johnson would take had been defined in Congress’ Reconstruction Acts, and it was closer to Lincoln’s than to the Ironclad Oath. Like Lincoln’s, it treated the leaders of the Confederacy with less mercy than it did enlisted men. Johnson had to swear that he had:

never been a member of any State Legislature, nor held any executive or judicial office in any State and afterwards engaged in insurrection or rebellion against the United States, or given aid or comfort to the enemies thereof;

that I have never taken an oath as a member of Congress of the United States, or as an officer of the United States, or as a member of any State Legislature, or as an executive or judicial officer of any State, to support the Constitution of the United States, and afterwards engaged in insurrection or rebellion against the United States, or given aid or comfort to the enemies thereof;

that I will faithfully support the Constitution and obey the laws of the United States, and will to the best of my ability, encourage others so to do.

So help me God.

Johnson had never been a state legislator, or a federal judge, or a member of Congress, so it would not have been a particularly difficult oath to take. The rebellion’s leaders would have to wait a bit longer to be allowed back into full political citizenship.

[J. Michael Luttig and Laurence H. Tribe: The constitution prohibits Trump from ever being president again]

The worst class of rebels, the oath seemed to argue, was those who had joined the attempted insurrection after already been elected or appointed to trusted positions of power—the ones that require an oath to support the Constitution. Both Lincoln and President Andrew Johnson had made similar exceptions for public officials who had rebelled, requiring a more difficult route to amnesty. The Fourteenth Amendment, which was then before the states for ratification, made the same distinction—as Donald Trump is now discovering.

Alfred M. S. Johnson went back to farming after that August day. Not long after, he had a son and named him Andrew Johnson—presumably in honor of the man who succeeded Lincoln in the presidency and had pardoned all ex-Confederates by the end of 1868.

Andrew Johnson eventually moved west to Hempstead County, Arkansas. There, he had a son named Garner James Johnson. As a young man, Garner Johnson left farming and moved to Shreveport, Louisiana, taking a job on the Kansas City Southern Railroad. He begat Raymond Ralph Johnson, who begat James Patrick Johnson, who begat James Michael Johnson.

On October 25, 2023, James Michael Johnson—better known as Mike Johnson—was elected the 56th speaker of the House of Representatives.

[Read: A speaker without enemies–for now]

Like his great-great-great-grandfather Alfred, Mike Johnson was part of an attempt to oust the duly elected government of the United States and replace it with one more to his liking. In Alfred’s day, the tools were secession and battle; Johnson’s were spurious claims of voter fraud and trumped-up legal arguments.

After Joe Biden’s victory over Donald Trump in the 2020 election, Mike Johnson worked hard to prevent the transition of power. In the days after the vote, he told interviewers that the allegations of rigged Dominion voting machines had “a lot of merit,” that there were “credible allegations of fraud and irregularity,” and that a voting system was “suspect because it came from Hugo Chávez’s Venezuela.”

In December 2020, Johnson organized an effort to get his fellow House Republicans to sign on to an amicus brief for a lawsuit challenging election results in the four states that would, if their votes were thrown out, give Trump a second term. He sent them all an email with the subject line “**Time-sensitive request from President Trump**” saying the president would be watching to see which GOP members of Congress signed on and which did not.

About three-quarters of the House Republicans who objected to the Electoral College count on January 6 cited legal arguments Johnson had made, leading The New York Times to call him “the most important architect of the Electoral College objections.” He gave what one fellow Republican member called “a fig-leaf intellectual argument” for overturning the election.

Johnson’s attempts were unsuccessful. The Supreme Court rejected the lawsuit in a brief, unsigned opinion. The 147 Congressional Republicans who, like Johnson, objected to the electoral vote count were outnumbered in the end.

But America was once again forced to ask: What do you do with men after they have fomented a rebellion against an elected government? After the Civil War, the federal response was generally lenient. Among the Confederacy’s top leaders, only Jefferson Davis served prison time, and then for just two years. President Johnson pardoned the overwhelming share of ex-Confederates barely a month after Lincoln’s assassination; he spent the remainder of his presidency pardoning the rest. Within a dozen years, conservative white southerners once again ruled the South—a control often achieved through great violence by former Confederate soldiers.

Mike Johnson didn’t lead a civil war, of course. But he did try to overturn an election and impose a president Americans hadn’t voted for. And it is striking how small the repercussions have been for those who did likewise. For members of Congress, opposing false claims of voter fraud has been much more politically dangerous than supporting them. Kevin McCarthy, Steve Scalise, Jim Jordan, and Tom Emmer each endorsed Johnson’s spurious legal arguments, and each has been nominated for speaker this year. And now, at the mention of Johnson’s actions, the House Republican caucus does little but laugh and boo.

I keep coming back to Alfred McDonald Sargent Johnson, Mike’s great-great-great-grandfather, and the oath he had to take that day in Cherokee County, pledging not to engage in rebellion again. Mike Johnson wasn’t a lowly foot soldier stuck in a war he played no role in starting. He was its architect, its author and finisher. And yet the only oath he’s been asked to take is as speaker of the House of Representatives.