After the guns fell silent at Appomattox, Washington went to war with itself.

The combatants, occupying opposite ends of Pennsylvania Avenue, battled over post-war Reconstruction. President Andrew Johnson, who favored a lenient approach to restoring civilian rule in the South, clashed with so-called Radical Republicans who believed conditions in the defeated Confederacy required vigorous federal intervention to protect the hard-won fruits of victory.

At stake was “[w]hether the tremendous war so heroically fought and so victoriously ended shall pass into history a miserable failure, barren of permanent results,” the abolitionist, former slave and prominent Republican Frederick Douglass wrote.

The ranks of the Radicals and their allies featured blacks and whites, practical politicians and visionary abolitionists. Their motives ran the gamut from genuine idealism to the hard-eyed political calculation that newly freed slaves could become a vital constituency for the Republican Party.

Andrew Johnson. (Library of Congress, Prints and Photographs Division)

Alexander H. Stephens. (Library of Congress, Prints and Photographs Division)

For his part, Johnson vowed to stand against Republican opponents who, he charged, labored to “pervert and destroy” the government with their Reconstruction policies. But beneath the veneer of Johnson’s proclaimed fidelity to the Constitution lurked a combative personality and deep-seated bigotry that drove his opposition to political equality for former slaves.

“He was a great fighter and not so good at making nice,” author and historian David O. Stewart said of Johnson. In addition to his taste for political pugilism, the humorless Johnson was a “thoroughgoing racist,” Stewart said. “He was a guy with real limits.”

Before it was over, the conflict between Johnson and the Radicals escalated into the first impeachment trial of a president. But in the dark days after the assassination of President Abraham Lincoln, some thought Johnson and the Radicals might get along.

During the war, Johnson had demonstrated a strong devotion to the Union and seemingly implacable hostility to slave-owning Southern planters as Tennessee’s military governor. His record as a Southern Democrat who opposed secession earned him his place as Lincoln’s vice-presidential candidate in 1864.

In a meeting between Johnson and members of the congressional Committee on the Conduct of the War, held shortly after Lincoln was shot, the new president vowed that “treason must be made infamous, and traitors must be impoverished.”

The Radicals, who had opposed Lincoln’s plans to speedily reintegrate rebellious states into the Union, took heart at the declarations of the new president. “We were all encouraged by this brave talk,” recalled Radical Republican George Julian of Indiana.

But Julian and his allies quickly became disillusioned with Johnson after he issued a pair of proclamations that set out a liberal course on Reconstruction. To hasten the return of civilian rule, the decrees outlined the process by which military occupation would end, protected property rights and offered immunity to most Southerners who swore loyalty to the U.S. government.

Beginning shortly after he took office, and continuing throughout the remainder of his presidency, Johnson also made energetic use of his power to issue pardons to defeated rebels. “At the present rate,” the Cincinnati Commercial observed in the summer of 1865, “the whole confederacy will apply for pardon before the 1st of August.”

The initiatives caused intense alarm among Republicans. It was “a profoundly tense moment, and Johnson didn’t do anything to ease those tensions,” said C. Joseph Genetin-Pilawa, an assistant professor of history at George Mason University. “Essentially he is thumbing his nose at the Republican Party.”

Johnson’s conduct wasn’t the only thing worrying Republicans.

Across the South, white voters returned rebel leaders to elective office. In Georgia, legislators sent former Confederate Vice President Alexander H. Stephens to the U.S. Senate.

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Newly freed slaves in Mississippi, Virginia, South Carolina and other states faced a reign of terror by vindictive whites. Southern states enacted “black codes” with the aim, according to J.W. Alvord of the Freedmen’s Bureau, of keeping former slaves “subservient to the white race and compelled to labor for low wages.”

When Congress convened on Dec. 4, Radical Republicans and their more conservative colleagues pushed back. The House and Senate barred the seating of Stephens and other lawmakers sent to Washington from the defeated South. Many were “persons fresh from the rebel congress or from the rebel army, men who could not take the requisite oath” to uphold the Constitution, said Republican Sen. Lyman Trumbull of Illinois.

Congress also created a Joint Committee on Reconstruction to investigate conditions in the former Confederacy. The evidence gathered by the panel in early 1866 confirmed the Radicals’ worst fears.

Few locations seemed more dangerous for former slaves than southern Mississippi. Capt. J.H. Matthews, assigned to the Freedmen’s Bureau, told lawmakers that vigilantes in Amite and Pike counties whipped and murdered former slaves. In a report to his superiors in the bureau, Matthews told of one ex-slave being hanged and skinned.

Outrages occurred elsewhere. The Rev. William Thornton, a black Baptist preacher from what is now Hampton, Va., testified that he had been threatened with death and that members of a church in a nearby county where he preached had been flogged simply for attending services.

“Did they not know they had a right to resist?” a committee member asked.

“They dare not do it,” Thornton replied.

South Carolina, where witnesses testified that whites routinely flogged, shot and whipped former slaves, seemed particularly unrepentant.

“The late slaveholders of South Carolina still believe that the loyal black man has no rights that they need respect, and have not been taught that hard lesson for them to learn: that they must treat those they once owned as free men and deal justly with them,” Gen. Rufus Saxton told the committee.

Johnson shrugged it all off. On Feb. 19 he vetoed legislation to extend the life of the Freedmen’s Bureau, established to assist former slaves as they made the transition to freedom. In March, he vetoed a civil rights bill and questioned whether former slaves possessed “the requisite qualifications to entitle them to all the privileges and immunities of citizens of the United States.” Congress overrode his veto of the civil rights bill, and eventually passed another version of the Freedmen’s Bureau legislation; Johnson vetoed this too, but Congress overrode.

At loggerheads with the Radicals, Johnson embarked on an unusual speaking tour in the summer of 1866 in the hopes of influencing the upcoming congressional elections. But the “Swing Around the Circle,” in which Johnson traveled to Philadelphia, New York, Cleveland, St. Louis and other cities with leading members of his administration, proved to be a political disaster.

As he attempted to convince Northern voters that he was defending the Constitution, Johnson traded insults with hecklers and embarrassed his supporters. “The President of the United States,” the New York Times warned, “cannot enter upon an exchange of epithets with the brawlers of a mob, without seriously compromising his official character and hazarding interests too momentous to be thus lightly imperiled.”

After the elections produced a landslide for Republicans, who won 173 of the 226 seats in the House and held 43 of 52 seats in the Senate, Johnson’s emboldened congressional foes began their counterattack.

Brig. Maj. Gen. Rufus Saxton. (Library of Congress, Prints and Photographs Division)

Edwin Stanton. (Library of Congress, Prints and Photographs Division)

Congress imposed military rule throughout the South to create new civilian governments that protected black voting rights and ratified the Fourteenth Amendment to the Constitution guaranteeing citizenship to anyone born in the United States.

Not content to reshape the South, Congress also took aim at the powers of the presidency. The Tenure of Office Act passed in March 1867, prohibited Johnson from dismissing a Cabinet member unless the Senate had approved a successor.

Simmering fury with the president boiled over at the end of the year. Johnson removed military commanders seen as sympathetic to the Radicals, and then further antagonized his foes with an annual message in which he asserted that blacks lacked the qualities required for self-government.

“It is the glory of white men to know that they have had these qualities in sufficient measure to build upon this continent a great political fabric,” the president declared. “But if anything can be proven by known facts — if all reasoning upon evidence is not abandoned — it must be acknowledged that in the progress of nations Negroes have shown less capacity for government than any other race of people.”

Goaded, the House Judiciary Committee approved articles of impeachment. The House rejected the measures by almost 2 to 1, but the Radicals remained at the ramparts. All they needed was another provocation.

It came Feb. 21, 1868, when the president dismissed Secretary of War Edwin Stanton, a Radical ally. Three days later, before deciding on the charges that would be sent to the Senate, enraged House Republicans voted overwhelmingly to impeach Johnson.

“The president,” Julian asserted, “as if to leave Congress wholly without excuse, has done an act which on its face settles the question of law, and shuts us up to the absolute necessity of taking the recreant usurper by the throat.”

Many of the articles of impeachment focused on the dismissal of Stanton, which appeared to violate the Tenure of Office Act. But the broadest charge against Johnson — Article XI — alleged that he had attempted to bring Congress into disrepute with intemperate denunciations of its opposition to his Reconstruction program.

Radical Charles Sumner of Massachusetts made his feelings about Johnson plain. “This is one of the last great battles with slavery,” he declared as he argued in favor of removing the Tennessean from office. Johnson embodied “the tyrannical Slave Power. In him it lives again. He is the lineal successor of John C. Calhoun and Jefferson Davis.”

More than half of the Senate favored removing Johnson from office, but the two-thirds majority required by the Constitution proved just out of reach. Johnson survived the first vote, on Article XI, by a single vote. Two charges pertaining to the dismissal of Stanton also failed by a single vote, and the rest of the case was dropped by the House.

Trumbull, who shared Sumner’s contempt for the president, voted to acquit. “If the question was, ‘Is Andrew Johnson a fit person for president?’ I should answer no,” the Illinois Republican conceded. But the case presented by the House failed to rise to the standards required to remove a president from office, he said.

Andrew Johnson (Library of Congress, Prints and Photographs Division)

Major General Benjamin F. Butler. (Library of Congress, Prints and Photographs Division)

Some votes may have been cast for less high-minded reasons. Suspicions that some senators were paid off to acquit Johnson hovered over the proceedings and moved Benjamin Butler, one of the House impeachment managers, to investigate.

Butler’s probe proved inconclusive, but Stewart said bribery may well have played a role in determining the outcome. “Our politics were really corrupt at a level we don’t appreciate,” he said. “It was a seamy time.”

As time passed, one of the Radicals began to have second thoughts about the vigor with which he had attacked Johnson. In his memoirs, published in 1883, Julian attributed the attempt to remove Johnson from office to overheated politics rather than concerns about Reconstruction.

“No extravagance of speech or explosion of wrath was deemed out of order during this strange dispensation in our politics,” Julian wrote. “Andrew Johnson was not the Devil-incarnate he was then painted, nor did he monopolize, entirely, the ‘wrong-headedness’ of the times.”

But the incendiary rhetoric of the period isn’t so difficult to understand. Involving issues of race, the enfranchisement of African Americans, and executive power vs. the prerogatives of Congress, Reconstruction was a political tinderbox that has left a legacy in some ways more enduring than the war itself. “In terms of creating the political fabric of our present day,” Genetin-Pilawa said, “Reconstruction is more important.”