Benedict Arnold's Treason (1780): Plot to Surrender West Point

Benedict Arnold’s treason was the attempt by one of the most capable generals of the American Continental Army to hand over the fortress of West Point, on the Hudson River in New York, to the British in September 1780. The plot collapsed when his British contact, Major John André, was captured carrying incriminating papers. Arnold escaped to the British, André was hanged, and Arnold’s name became a byword for betrayal in the United States.

Arnold the Patriot hero

Born in Norwich, Connecticut, in 1741, Benedict Arnold became a merchant and ship-owner in New Haven before the American Revolution. In May 1775 he joined Ethan Allen in capturing Fort Ticonderoga, and later that year led an exhausting march through the Maine wilderness to attack Quebec, where he was badly wounded in the Battle of Quebec on 31 December 1775.

In October 1776 his improvised fleet on Lake Champlain fought the Battle of Valcour Island, delaying a British advance by a year. In 1777 he played a leading part in the Battles of Saratoga, where on 7 October he was shot in the same leg wounded at Quebec. Many contemporaries regarded him as the army’s boldest field commander.

Grievances and debts

Arnold’s career was also marked by quarrels. In February 1777 Congress promoted five junior brigadiers over him to major general, and although he was later promoted, his seniority was not restored for some time. He was repeatedly accused of misusing funds, and he resented what he saw as ingratitude for his wounds and sacrifices.

Unable to serve in the field after Saratoga, he was made military governor of Philadelphia in June 1778 after the British withdrawal. He lived lavishly, ran up debts and clashed with Pennsylvania’s radical government, which brought charges against him. In April 1779 he married Margaret “Peggy” Shippen, the young daughter of a prominent family with Loyalist sympathies, who had known British officers, including John André, during the occupation.

Secret correspondence

From May 1779 Arnold began a secret correspondence with the British headquarters in New York, using intermediaries and coded letters. His contact was John André, aide and later adjutant general to the British commander, Sir Henry Clinton. Arnold supplied information on American troop movements and bargained over his price.

In early 1780 a court-martial cleared him of most charges but ordered a reprimand, which Washington delivered mildly in April. Arnold then sought the command of West Point, which Washington granted in August 1780. West Point controlled the Hudson River and the link between New England and the other states, making it one of the most important American posts.

Arnold asked for £20,000 if the fortress and its garrison of about 3,000 men fell into British hands. To make capture easier he weakened the defences, for example by sending troops away and neglecting repairs.

The plot discovered

On the night of 21 September 1780 André came ashore from the British sloop HMS Vulture to meet Arnold near Haverstraw on the west bank of the Hudson. Their meeting ran on until dawn, and American guns then fired on the Vulture, forcing it to move downstream. André had to return to British lines by land, out of uniform, carrying a pass from Arnold in the name “John Anderson” and papers about West Point hidden in his stockings.

On 23 September, near Tarrytown, three American militiamen, John Paulding, Isaac Van Wart and David Williams, stopped him. When he mistakenly assumed they were Loyalists and revealed he was a British officer, they searched him and found the documents. The officer in charge, Lieutenant Colonel John Jameson, sent the papers to Washington but also sent a report to Arnold.

That message reached Arnold on the morning of 25 September at his headquarters across the river from West Point, just before Washington was due to arrive. Arnold left at once, was rowed down the Hudson and escaped aboard the Vulture. Washington arrived soon afterwards, learned of the plot and reinforced West Point. Peggy Arnold, in an apparent fit of hysteria, persuaded Washington’s officers that she knew nothing.

The fate of John André

André was tried by a board of senior officers presided over by Major General Nathanael Greene. Because he had been captured in disguise behind American lines with a false name and secret papers, the board found him to be a spy. Clinton tried to save him, and some Americans privately suggested exchanging him for Arnold, but the British would not give Arnold up.

André asked to be shot as a soldier rather than hanged, but Washington refused. He was hanged at Tappan, New York, on 2 October 1780. His courage and charm won sympathy on both sides, and in 1821 his remains were moved to Westminster Abbey. The three militiamen received pensions and a silver medal from Congress.

Reaction in America

News of the plot caused shock across the states. Arnold had been one of Washington’s most trusted generals, and the discovery that he had sold himself to the enemy came during a bleak year marked by the fall of Charleston, mutinies over pay and a collapsing currency. General orders issued in the main army’s camp by Nathanael Greene announced that treason had been discovered and praised the providence that had exposed it in time.

Crowds in Philadelphia paraded an effigy of Arnold with two faces and burned it, and his property in Pennsylvania was confiscated. His name quickly entered American speech as a synonym for traitor. Paradoxically, the affair also gave Patriots a rallying point: the plot had failed, and the militiamen who caught André were celebrated as examples of virtue.

Arnold in British service

Arnold received about £6,000 and a commission as a brigadier general in the British army. In January 1781 he led a raid in Virginia that burned parts of Richmond, and in September 1781 he attacked New London in his native Connecticut, where many defenders of nearby Fort Griswold were killed after it fell.

After the British surrender at Yorktown, Arnold sailed for Britain in December 1781. He never received the senior command he hoped for, traded unsuccessfully in Canada and the Caribbean, and died in London on 14 June 1801. Peggy Arnold died in 1804.

Myths and facts

Myth: Arnold acted only for money. Money mattered, but historians also stress his wounded pride, his conflict with Congress and Pennsylvania authorities, and his opposition to the French alliance. His motives were mixed.

Myth: Peggy Shippen was an innocent bystander. Letters later found in Clinton’s papers indicate that she passed messages and knew of the plot, although the full extent of her role is still debated.

Fact: his earlier service is still recognised. At Saratoga National Historical Park a monument shows only a boot and epaulette, honouring his wounded leg without naming him.

Timeline

• 1741, 14 January: Benedict Arnold is born in Norwich, Connecticut.
• 1775, 31 December: Arnold is wounded in the attack on Quebec.
• 1777, 7 October: Arnold is wounded again at Saratoga.
• 1779, May: Arnold opens secret correspondence with the British.
• 1780, August: Arnold takes command of West Point.
• 1780, 21–22 September: Arnold meets André near Haverstraw.
• 1780, 23 September: André is captured near Tarrytown.
• 1780, 25 September: Arnold escapes to HMS Vulture.
• 1780, 2 October: André is hanged at Tappan.
• 1801, 14 June: Arnold dies in London.

Why it matters

Arnold’s treason came at a low point for the American cause and showed how fragile it was, yet its discovery strengthened Patriot resolve. West Point stayed in American hands, and Arnold’s transformation from hero to traitor made his name one of the most enduring symbols of betrayal in American history.