How Did Benedict Arnold Become America's Most Infamous Traitor?

It's a measure of Arnold's infamy that nearly two centuries after his death, he remains so reviled that Americans still sometimes refer to someone viewed as disloyal as a "Benedict Arnold." That's true even though, as Sheinkin notes, the targets of that invective and their offenses usually don't measure up to Arnold's extreme level of treachery.

"Arnold's case is so disturbing not because he decided to back the British, which many others in America did," explains Eric D. Lehman via email. He's an associate professor of English at the University of Bridgeport, and author of "Homegrown Terror: Benedict Arnold and the Burning of New London," a 2015 book on a war crime committed by Arnold after he joined the British side. "It is because he was a hero to the American side first, because he had so many friends and comrades who fought beside him. To fight beside someone, and then to switch sides and fight against them, as he did in Virginia and Connecticut after the West Point debacle, is anathema to most people. It is so much more troubling than mere 'political' betrayal, and that is why it is so incredibly rare, particularly for a general in the army."

Lehman sees parallels between Arnold and another infamous figure in early American history, Aaron Burr, who not only killed Alexander Hamilton in a duel, but also was tried unsuccessfully for treason for his role in an ill-fated plot to lure states to leave the U.S. and join a new empire.

"Both were competent war heroes who in one way or another had their careers stalled or ruined by their own actions, and then plotted against their perceived enemies in the American government," Lehman explains. "Both had the misperception or flaw that the government was the nation, and when elements in that government — in Arnold's case Congress or in Burr's case Thomas Jefferson — became antagonistic to them, they responded by trying to burn the whole thing down."

In some ways, Arnold's traitorous nature may have been forged by resentment and frustration. Born in Norwich, Connecticut, in 1741, he spent his youth being groomed to attend Yale, but the bankruptcy of his alcoholic father dashed those dreams. He instead apprenticed as an apothecary — the 18th century version of a pharmacist — and served in the French and Indian War, before settling in New Haven, Connecticut, where he built a drugstore business and worked as a merchant and sea captain involved in the trade with the West Indies and Canada. By the time Arnold was in his mid-30s, he had become successful enough to build one of the grandest homes in New Haven, according to Nathaniel Philbrick's 2016 Smithsonian profile of Arnold. But Arnold was never quite content.

"He had great gifts of intelligence and physical prowess, but he always felt that they were being overlooked, first as a boy, then in the military during the Revolution," Lehman says. "He had the sort of prickly personality that took offense very easily. He was often threatening to quit or to fight a duel with someone who insulted him. I would say that he was certainly a narcissist, but the tragedy is that he could have gone another way. He had a lot of people pulling for him, helping him and loving him. But he ultimately chose to betray many of them."

In the spring of 1775, Arnold was serving as captain of a local militia in New Haven when the British attacked Lexington and Concord. According to Philbrick, Arnold grabbed part of New Haven's gunpowder supply and headed to Massachusetts to join the fight. Early on, Arnold distinguished himself as a competent, even gifted military leader, but one who frequently became immersed in political squabbles that stymied his rise. Arnold got Massachusetts officials to back his plan to capture Fort Ticonderoga in New York, so that the Americans could seize its 80 or so cannons. But as it turned out, Arnold wasn't the only one who wanted that artillery, and when he got to New York with his expedition, he was compelled to team up with Ethan Allen and his Green Mountain Boys. The Americans rowed across Lake Champlain from what is now Vermont and staged a daring, late-night surprise attack to seize the fort, a major early victory in the war. Though Arnold and Allen co-led the raid, Allen — who brashly demanded that the British surrender "In the name of the Great Jehovah and the Continental Congress" — ended up with more of the credit.

Arnold had even bigger ambitions. He pitched George Washington, the new head of the American forces, and the Continental Congress on a scheme to invade Canada, overwhelm the few hundred troops that the British kept there, and embolden Canadian colonists to join the American cause. Washington agreed, but appointed Maj. Gen. Richard Montgomery to head the effort and relegated Arnold to commanding a small force that made its way through the Maine wilderness to Quebec City. As this 1990 article by historian Willard Sterne Randall describes, the New Year's Eve assault on the Canadian city turned into a debacle, in which Montgomery was killed. Arnold, though severely wounded, managed to rally the remaining troops and continue the siege until spring, when he was ordered to return home.

Arnold went on to distinguish himself in September 1777 in the battle of Saratoga. He quarreled with Maj. Gen. Horatio Gates, his commander, who tried to keep him back at headquarters as a punishment. But Arnold eventually ignored his orders and rode his horse to the front, where he led a charge that outflanked and routed a force of German mercenaries. During the fighting, Arnold was shot, and a bullet killed his horse and caused it to fall upon him, crushing the leg he'd injured in Quebec. He had to be carried off the field and walked with a limp for the rest of his life.

Arnold's courage had helped the Americans win a crucial victory, but again, he didn't get the credit he deserved. Instead, in July 1778, Washington put Arnold in charge of the city of Philadelphia, which the British had abandoned. Kept out of the action, Arnold married the young daughter of a local judge, Peggy Shippen, and the couple lived an extravagant lifestyle that was beyond an American general's means. Congress refused to pay some of his expense vouchers, and eventually, in June 1779, he was court-martialed on charges of corruption.

Though Arnold eventually was acquitted, the humiliation might have been the final straw. Even before the trial began, he secretly reached out to the British, and began communicating with British spy Maj. John Andre through coded correspondence. Arnold asked to be reassigned to West Point, the fort that served as Washington's headquarters. In September 1780, he met with Andre at a house near the Hudson River and hatched a plot to hand the fort over to the British, in exchange for 20,000 British pounds (equivalent to £3,613,470.99 or $4,674,747.42 in 2020 currency) — 6,000 if the scheme failed — and a command in the Royal Army.

But once again, Arnold was foiled by fate. Before Andre could make his way back into British-held territory, he was captured by American militiamen. Arnold learned of Andre's fate and managed to escape on the Hudson in a British ship, the Vulture, before he could be arrested. From on board, Arnold wrote a letter to Washington, complaining of "the ingratitude of my country" but asking that his former superior protect Arnold's wife from Americans' vengeance. "It ought only to fall on me," he wrote.

Arnold's betrayal of the colonial cause went beyond just his effort to hand West Point over to the British. In 1781, as a British officer, he ordered his troops to burn New London, Connecticut, just 10 miles (16 kilometers) away, where he had been born and raised, ostensibly to punish privateers who operated out of New London for capturing a British merchant ship. Arnold's forces torched 140 buildings, including residents' homes, and after capturing the fort overlooking the town's harbor, slaughtered 70 American militiamen who had surrendered.

"I think that once Arnold made the choice to go over to the British he knew he had to succeed, and was willing to do anything to make that happen," Lehman explains. "That's a dangerous place to be in for anyone, and it led him to a very dark place."

In December 1781, Arnold and his wife and children went to England, where they lived for a time in London, supported in part by the portion of the fee that he'd been guaranteed for the failed West Point plot. He later moved to Canada and tried to revive his career as a merchant. But his fortune was mostly gone by the time that he died in 1801.

"This is a classic rise and fall story," says Sheinkin. "We see them over and over, and of course it's usually some character flaw that brings the hero down. That's not just in fiction and theater — that has happened throughout history and will continue to happen."

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