As plans for President Donald Trump’s big military parade are slowly beginning to take shape, it is worthwhile recalling an incident that occurred during the biggest military parade in U.S. history—the Grand Review of the Armies in May 1865 at the end of the U.S. Civil War—which may have impacted the subsequent role of the U.S. military in American politics and society.

As the victorious 60,000-strong Armies of the Tennessee and Georgia, commanded by eccentric and willful Gen. William Tecumseh Sherman, marched down Pennsylvania Avenue on the second day of the colossal military spectacle on May 24, onlookers were not merely interested in the battle-hardened, rough-looking soldiers that had smashed Confederate forces in the West and cut a path of destruction through Georgia and the Carolinas. Rather, they were anxiously awaiting what would happen when Sherman met U.S. Secretary of War Edwin Stanton on the reviewing stand.

Recommended: The 5 Biggest Nuclear Bomb Tests (From All 6 Nuclear Powers).

Recommended: How Israel Takes U.S. Weapons and Makes Them Better.

Recommended: North Korea’s Most Lethal Weapon Isn’t Nukes.

As many contemporary observers noted, once Sherman reached the reviewing stand, he dismounted and went up the platform to greet the dignitaries, including U.S. President Andrew Johnson and his old friend Ulysses S. Grant, the commanding general of all U.S. forces. The historian William Marvel in his book Lincoln’s Autocrat: The Life of Edwin Stanton recounts what happened next:

[W]hen a hopeful Stanton extended his hand Sherman let him grasp the air with it, clapping his own hand to his side and merely nodding or bowing slightly. Across the avenue sat others who had been waiting for this very moment, many of whom had trained binoculars or opera glasses on the tall, florid general and the squat, grey bureaucrat.

One observer noted: “Sherman’s face was scarlet, and his red hair seemed to stand on end.” Julia, the wife of Ulysses S. Grant wrote: “What a defiant and angry glance he shot at Stanton.”

Sherman proudly recalled in later life: “As I approached Mr. Stanton, he offered me his hand, but I declined it publicly and the fact was universally noticed.” Rumors even circulated after the parade that Sherman had called Stanton “nothing but a damned clerk”, which, however, turned out to be false.

What had caused this public rift between one of the Union’s most respected generals and an iconic member of Lincoln’s wartime government on a day dedicated to celebrating the end of a war that killed over 750,000 Americans and that the former called “the happiest and most satisfactory moment of my life”?

The short answer: bruised egos and personal ambitions. Among other things, Stanton thought Sherman was fishing for the “Copperhead nomination for President.” A longer exposé, nonetheless, would need to emphasize the secretary of war’s (unfounded) fear of a military takeover of the government in 1865 by an officer who may have become too powerful as a result of the conflict to be reined in by civilian authorities. In April 1865, Stanton was the driving force in convincing the government and the North’s public that Sherman had overstepped his authority when he negotiated a surrender agreement with Confederate Gen. Joseph E. Johnston in North Carolina, directly accusing him of insubordination and indirectly—via leaks to the press of government bulletins—of treason. The results were predictable. Sherman felt publicly humiliated, willfully maligned and double-crossed by Stanton.

The disagreement between the two provides an excellent case study of a crisis in civil-military relations in nineteenth-century America. In an e-mail exchange, Richard H. Kohn, offers a notional definition of such a crisis broadly dividing it into two categories: “First is the defiance of orders, or knowing insubordination. Second is one of exceeding one’s authority as a senior military officer that causes real political or other difficulty or crisis.” The Sherman-Stanton rift touches both categories. According to Stanton and other politicians, Sherman knowingly defied orders and caused real political difficulties to the administration as is shown below.

Stanton: The Dick Cheney of His Day

That such a civil-military skirmish would involve Edwin Stanton is not surprising. Stanton, whom the historian William Marvel called the “Dick Cheney of the Lincoln Administration,” was seen as Lincoln’s power hungry and autocratic lieutenant. Although successfully reforming the War Department, including curtailing rampant corruption and boasting superb organizational skills, he was careful to husband his own personal influence and authority under the guise of the military necessity to expand the federal government’s reach in wartime.

For example, it was primarily Stanton who persuaded the Lincoln cabinet to seize extra constitutional powers including suspending habeas corpus and the power to make extraordinary arrests without due process. He also took military possession of telegraph lines to exert control over the North’s media and, in a revealing episode to sideline military leadership, removed the telegraph line from Army Headquarters and installed it in the War Department, which prevented the commanding general (George McClellan at the time) from directly communicating with the White House.

It was also Stanton who unilaterally decided to try the Lincoln assassination conspirators in military court behind closed doors despite stiff public opposition. This was partially based on his conviction that the Confederate government in Richmond was involved in the killing of the U.S. president. Yet, he also had personal reasons for wanting to be seen as tough on the South: He sought to ingratiate himself with Radical Republicans committed to an extreme form of Reconstruction, as well as to the incumbent U.S. president Andrew Johnson, who initially sought to inflict a severe punishment on the South for the rebellion (Johnson would later reverse course).

In many ways, the cantankerous but shrewd political operative Stanton was the antidote to the egocentric yet upright soldier Sherman. Indeed, the fast-talking general, always a bundle of nervous energy, was open in his disdain of politics and politicians, although one of his brothers served as a U.S. senator. When asked later whether he would stand as the Republican candidate for president, Sherman barked: “I will not accept if nominated and will not serve if elected.” What Stanton and Sherman shared, however, was a ruthlessness when opposed, paired with an oversensitivity to criticism, often culminating in a take-no prisoners attitude when challenged. Both were also prone to hyperbole.

Johnston’ Surrender

Following the surrender of Robert E. Lee’s Confederate Army of Northern Virginia to Ulysses S. Grant at Appomattox Court House on April 9, 1865, the only remaining large Confederate force in the Eastern theater of operations was under the command of Joseph E. Johnston encamped in North Carolina facing Union armies under Sherman. On April 17 and 18, Johnston and Sherman negotiated an intricate surrender convention based on the terms Grant conceded to Lee at Appomattox and which Sherman had called “magnanimous and liberal.” They were joined by Confederate secretary of war John Breckinridge.

Although, in a letter to Grant vouching that he would “be careful not to complicate any point of civil policy,” Sherman, in his draft, in the words of William Marvel “proposed nothing less than a blueprint for Reconstruction, including a general amnesty, the restoration of citizens’ political rights, and the preservation of state governments.” Sherman claimed to have acted in the spirit of Abraham Lincoln: “Recalling the conversation of Mr. Lincoln at City Point [where Lincoln vaguely promoted a policy of leniency to the South], I sat down at the table and wrote off the terms, which I thought concisely expressed this views and wishes, and explained that I was willing to submit these terms to the new President.”

As James Lee McDonough in his biography of Sherman notes:

He had entered into terms of a political nature. His document recognized the existing state governments in the South, effective as soon as their members took an oath of allegiance to the United States. (…) His terms sanctioned the reestablishment of Federal courts in the South, and guaranteed “the political rights and franchises” of the Southern people, “as well as their rights of persons and property.” The terms seemed even to leave a possibility of recognizing the Confederate war debt. Sherman also indicated that no one was to be punished “by reason of the late war, so long as they live in peace and quiet.”

Interestingly, the document did not specifically address the issue of slavery, although Sherman said that Johnston and Breckinridge “admitted that slavery was dead.” He also noted that he “could not insist on embracing it in such a paper, because it can be made with the states in detail.” His major concern, Sherman later wrote, was to prevent the breakup of Rebel forces into guerilla bands. Nevertheless, the agreement Sherman sent for presidential approval to Washington on April 18 outlined the postwar status of seceded states. In short, Sherman had negotiated a full-blown peace treaty with the Confederacy—vicariously usurping both congressional and presidential powers.

Upon reviewing the agreement, Grant advised Stanton and President Johnson to immediately summon an emergency cabinet meeting to discuss the terms. Stanton repeatedly insinuated to cabinet members that Sherman’s action did not merely constitute insubordination—but treason. The cabinet rejected the agreement with the U.S. president now also calling Sherman an outright traitor. Stanton “waxed especially vitriolic on Sherman,” according to Marvel. “Stanton reacted as if Sherman had penned an unalterable treaty rather than a proposal to be duly considered,” McDonough writes. Ron Chernow in his book, Grant, notes that the secretary of war seized the opportunity to pursue a vendetta against Sherman and “turn him into a public pariah.” Grant harshly called Stanton’s actions “that inexplicable and cruel storm of defamation.”

After the cabinet rejected the agreement, Stanton ordered Grant “to immediately proceed” to North Carolina and “direct operations against the enemy,” which in fact meant relieving Sherman of his command. Grant, however, said nothing of the political consternation that his draft agreement had caused in Washington and also did not reveal that he was to assume command when he arrived at Sherman’s headquarters. Grant merely noted that the agreement had been rejected and that Sherman should offer Johnston identical terms to those he offered to Lee at Appomattox. Johnston eventually agreed to the new terms, sweetened by 250,000 rations for his starved troops, and surrendered his forces on April 26 in what would be the largest single capitulation of Confederate armies in the war.

The day before, Sherman had sent a note to Stanton stating:

I admit my folly in embracing in a military convention any civil matters, but unfortunately such is the nature of our situation that they seem inextricably united and I understood from you (…) that the financial state of the country demanded military successes, and would warrant a little bending to policy.

Rupture in Civil-Military Relations

Sherman would only find out days later about the true nature of the defamatory campaign Stanton had launched against him. In order to further anti-Southern sentiments following the assassination of Lincoln in the North and to humiliate Sherman, Stanton leaked the draft agreement to the press along with other government bulletins and personal correspondence including a letter in which he openly called the general “a common traitor and a public enemy” who instructed his soldiers to disobey the secretary of war’s “lawful orders.” Stanton also insinuated that Sherman may have been influenced by Confederate sympathies and possibly helped the escape of the president of the Confederate States of America Jefferson Davis—a charge repeated by U.S. president Andrew Johnston—who was still at large at that time. It turns out that this charge was initially leveled by a jealous fellow officer, Gen. Henry Halleck.

As the Prussian statesman Otto von Bismarck would do a decade later, the secretary of war also carefully edited a telegram that Grant had sent him discussing Sherman’s actions, which noted that Sherman had acted in good faith and did not intend to cause controversy. Stanton, however, leaked two sentences of the document to the press, which merely said that the truce with Johnston was terminated and once more admonishing that “civil matters could not be entertained in any convention between army commanders.” The full telegram was only found after Stanton’s death in 1869.

Stanton was not just trying to rein in a general who ostensibly had become too powerful. For example, the secretary of war never sent Sherman a copy of a March 3 telegram he had sent to Grant on behalf of Lincoln reiterating that Grant “was not to decide, discuss, or confer upon any political question. Such questions the President holds in his own hands, and will submit them to no military conferences or conventions.” It is unclear why Stanton never conveyed these instructions to Sherman. One explanation is that the two had already clashed over a number of issues pertaining to the Union’s Western Armies and the conduct of the war. A more convincing explanation might be the radical different political outlook of the two protagonists.

Sherman was known to have sympathies for the Southern way of life. “In many ways, Sherman wanted to re-create the status quo ante in southern states, minus slavery,” Chernow writes. McDonough notes that Stanton was infuriated by Sherman’s reactionary attitude against blacks serving in the Union armies. Marvel perhaps offers the most convincing argument when he summarizes Gideon Welles’ analysis of Stanton’s rationale for his ferocious attack:

Looking back on Stanton’s disproportionate alarm, Welles thought he regarded peaceful reunion with intense trepidation because, as a turncoat from the ranks [Stanton had switched his political allegiance] of state-rights conservatives [to Radial Republicans], Stanton (…) feared a rapid restoration of the old Union.

Had Sherman’s agreement with Johnston come into effect, it would have brought defeat to the Radical Republican agenda to which Stanton had pledged his allegiance and might have ended his political career.

Once Sherman was aware of Stanton’s actions, he was both shocked and outraged. According to a Union officer, Sherman “unbosomed himself with an eloquence of furious invective which for a while made us all stare.” Some of those invectives can be found in this New York Times article from May 1865. In a letter to Grant he wrote that, “a great outrage has been enacted against me…My officers and men feel this insult as keenly as I do.” He went on: “Mr. Stanton must publicly confess himself a Common libeler.” Sherman melodramatically concludes the letter with a Shakespearean reference laying bare his contempt for politics: “The lust for Power in Political minds is the strongest passion of Life, and impels Ambitious Men (Richard III) to deeds of Infamy.” When he marched his army to Washington, there were repeated rumors—believed by a number of members in the administration—that he intended to seize power and arrest cabinet members including Stanton.

Consequently, “Stanton grew frantic (…) suspecting that the general intended to lead his armies against the government,” Marvel writes. “Stanton’s raving seemed to infect his protégé, Speed [U.S. Attorney General], who even wondered whether Sherman might arrest his best friend, Grant, when he arrived.” Aware of the rumors that he intended to seize power, Sherman told an Union officer when he arrived on the outskirts of Washington: “Let some newspaper know that the vandal Sherman is encamped near the canal bridge…Though in disgrace, he is untamed and unconquered.” When Sherman met the president in the White House, the latter denied advance knowledge of the Stanton leaks. He was also summoned to testify in front of the congressional Committee on the Conduct of the War, controlled by Radical Republicans, where he once more had to justify his draft agreement with Johnston. It left him utterly disgusted.

The largest military parade in U.S. history and the fateful encounter between Sherman and Stanton occurred two days after his testimony. Neither before, nor after the parade did Stanton offer an apology to Sherman. Halleck would eventually apologize for his insinuations, but Sherman rejected it. This would have repercussions in the weeks to follow.

Sherman’s men of the Army of the Tennessee and the Army of Georgia were intensively loyal to their commander and were aware of his feud with the secretary of war. In the days following the parade, they publicly displayed their contempt for him. Stanton did not dare to arrest them for fear of inciting violence. According to Ulysses S. Grant in a report to Sherman, some of his Western officers were at the Willard Hotel “drinking and discussing violently the conduct of Mr. Stanton,” punctuated by occasional leaps on the bar counter calling for “three groans for Mr. Stanton.” Soldiers openly taunted Stanton, who feared for his life. It was a dangerous situation and both Sherman and Grant were concerned over losing discipline of thousands of troops stationed in the city and encamped on its outskirts. Next to the delicate Stanton affair, the two generals also feared the deep rivalry of eastern (Army of the Potomac) and western Union forces (Sherman’s Armies of the Tennessee and Georgia).

Concerns over the feud grew so desperate that Sherman’s wife even tried to heal the breach by making a courtesy call on Stanton and his wife, which they welcomed but Sherman refused to give in without an official apology from the secretary of war. The consequences of the rift were unique in American history. “The tense situation among Sherman’s soldiers may have accelerated the process of mustering out the armies,” Marvel speculates. “On May 29, Stanton ordered all troops sent home whose terms of service would expire before October; that included the greater part of Sherman’s four corps and the vast majority of his most loyal officers and men.” In despair for his own safety and that of the government, the secretary of war apparently decided to prematurely disband U.S. military units to prevent domestic insurrection.

The Consequences

The Stanton-Sherman dispute, at least according to Stanton and his acolytes, threatened the sanctity and security of the civilian government. Sherman denied any such designs and it was not taken seriously by anyone who knew him. For Sherman, however, these defamations were yet another confirmation of the despicable nature of politics. “Washington is as corrupt as Hell,” he wrote in a letter, and he intended to “avoid it as a pest house.” Yet his feud with the secretary of war, no doubt not foreseen by Stanton, contributed to establishing an important precedent in what role the military should and should not have in a democracy: It helped keep the U.S. military out of politics.

Markedly, the Stanton-Sherman disagreement was not that unusual. Throughout the nineteenth century, the secretary of war and commanding general of the army had ill-defined and often overlapping responsibilities. This ambiguity triggered public controversy including a rift between Jefferson Davis and General Scott in the 1850s, continuous fights between Stanton and George McClellan during the civil war, fierce arguments between Sherman and William Belknap in the 1870s, as well as disputes between the army’s top military officer and the war secretary during the Spanish-American War in 1898, as Samuel P. Huntington points out in his seminal work The Soldier and the State. However, Sherman, when he was commanding general of the army from 1869 to 1883, was instrumental in guaranteeing that such disagreements gradually would be less of a concern for his successors by not only installing a sense of professionalism in the army, but also by defining and further solidifying the military’s role in American society.

“His outlook and thought were thoroughly military, and the professional spirit which he manifested permeated throughout the ranks of the officer corps,” Huntington writes. Not only objecting to the use of the military as a police force, Sherman was also “particularly adamant in stressing the divorce of the military from politics,” according to Huntington. Most importantly, Sherman insisted that “no Army officer should form or express an opinion” on party politics. The side product of this divorce, however, was a growing civil-military gap and an alienation of the military from the rest of society in the later nineteenth century which persists to this day. Yet, Huntington notes that with Sherman begins the tradition of political neutrality of the U.S. armed forces—a key ingredient to the proper functioning of a democratic government.

Whether this would have happened without the Sherman-Stanton feud is an uncertain historical counterfactual. Given Sherman’s aversion to politics prior to the dispute, its absence likely would not have substantially altered the course of history. Yet a good argument can be made that the Sherman-Stanton feud—which had its unique public manifestation during the Grand Review of the Armies in May 1865—at least vicariously contributed to stable civil-military relations in the United States in the long run. It is also one of the few instances of a civil-military dispute threatening to turn violent. In that sense, the rift remains a somewhat understudied subject. No other U.S. military officer after Sherman unilaterally drafted a peace treaty that included a plan for postwar reconstruction and secured the signature of the erstwhile enemy. That alone makes it an interesting episode to ponder.

Whether Donald Trump’s feuding or his military parade will yield a similar interesting historical vignette for future generations or produce a positive side-effect remains to be seen.

Franz-Stefan Gady is a Senior Editor with The Diplomat.