25
Sep
1780
Arnold's Treason Discovered
West Point, NY· day date
The Story
# Arnold's Treason Discovered
In the autumn of 1780, the American Revolution hung in a precarious balance. The Continental Army was exhausted after five years of war, plagued by chronic shortages of food, clothing, and pay. Morale was dangerously low, and the alliance with France, though promising, had yet to deliver a decisive victory. It was against this backdrop that one of the most shocking betrayals in American history unfolded at West Point, the strategically vital fortress perched above the Hudson River in New York. Had the plot succeeded, it might well have broken the back of the American cause.
Benedict Arnold had once been among the most celebrated generals in the Continental Army. His extraordinary courage at the battles of Saratoga in 1777 had helped secure the pivotal American victory that brought France into the war. But Arnold was also a man consumed by grievance. Despite his battlefield heroics, he felt overlooked for promotions, underpaid, and insufficiently honored by the Continental Congress. A serious leg wound suffered at Saratoga left him in constant pain and limited his ability to command in the field. After being appointed military governor of Philadelphia in 1778, Arnold lived extravagantly beyond his means and faced accusations of corruption from both civilian and military authorities. His marriage to Peggy Shippen, a young, well-connected Philadelphia socialite with ties to British officers, only deepened his entanglement with the enemy. By 1779, Arnold had secretly opened a correspondence with the British through Major John Andre, the charming and capable chief intelligence officer serving under British General Sir Henry Clinton. Arnold offered to hand over West Point — the fortress Washington considered the key to controlling the Hudson River and keeping the northern and southern states connected — in exchange for money and a commission in the British Army.
Arnold maneuvered to secure command of West Point in the summer of 1780 and immediately began weakening its defenses, dispersing troops, and allowing fortifications to deteriorate so that a British assault would meet minimal resistance. He passed detailed plans of the fortress, troop dispositions, and other sensitive military intelligence to Andre during a secret meeting behind American lines on the night of September 21, 1780. Andre, traveling overland back toward British lines in civilian clothes and carrying the incriminating documents hidden in his stockings, was stopped on September 23 by three American militiamen near Tarrytown, New York. The papers they discovered left no doubt about the nature of the conspiracy.
On the morning of September 25, 1780, General George Washington was traveling to West Point for a routine inspection, accompanied by members of his staff including his trusted aide-de-camp, Alexander Hamilton. While Washington was still en route, word of Andre's capture and the damning documents reached his aides. Arnold, who had been expecting Washington at his headquarters across the river, received his own warning that Andre had been taken. Realizing his treachery was about to be exposed, Arnold made a desperate escape, racing to the Hudson River and boarding the British sloop HMS Vulture before Washington could arrive. When Washington reached the Arnold residence, he found the general gone, the fortress deliberately weakened, and Peggy Shippen Arnold in a state of apparent hysterical distress — a performance many historians believe was calculated to deflect suspicion from her own involvement in the conspiracy.
Hamilton and the other officers present acted swiftly, working to shore up West Point's defenses and alert nearby commands to the possibility of an imminent British attack. Washington, stunned by the betrayal of a man he had trusted and championed, reportedly uttered words to the effect that Arnold had gone over to the enemy and that West Point was in danger. Major Andre, unlike Arnold, did not escape. He was tried by a military tribunal, found guilty of spying, and hanged on October 2, 1780, a fate that even many Americans regarded with sadness given his dignity and composure throughout the proceedings.
Arnold's treason reverberated far beyond West Point. Paradoxically, the discovery of the plot may have strengthened rather than weakened the American cause. The shock of betrayal galvanized the Continental Army and the public, reinforcing their commitment to independence and reminding them of what was at stake. Arnold's name became an enduring synonym for treachery in the American vocabulary, while the near-disaster at West Point underscored the fragility of the Revolution and the extraordinary vigilance required to see it through to its ultimate success.
People Involved
Benedict Arnold
Continental Army General
The brilliant Continental officer who, as commander of West Point in 1780, conspired to surrender the fortress to the British. His treason plot was exposed when his contact Major Andre was captured, and Arnold fled to the British lines.
Major John Andre
British Intelligence Officer
Charming British officer who served as the intermediary in Arnold's treason. Captured behind American lines carrying plans of West Point's defenses, he was tried and hanged as a spy despite widespread sympathy for his personal conduct.
Alexander Hamilton
Washington's Aide-de-Camp
Hamilton was present at the dramatic moment when Arnold's treason was discovered, and he led the frantic effort to secure West Point before the British could act. He later advocated for leniency toward Andre, whose dignified conduct impressed even his captors.
Peggy Shippen Arnold
Arnold's Wife
Philadelphia socialite who married Benedict Arnold and maintained connections with British officers including Andre. Long dismissed as an innocent bystander, modern scholarship suggests she was deeply involved in facilitating the treason plot.