September 21, 1780: Benedict Arnold commits treason against his country.

You are there: Born in 1741, Benedict Arnold is the fourth member of his family named after his ancestor, an early colonial Governor in Rhode Island. His father is a successful merchant in Connecticut until alcoholism leaves the family in financial straits and the son without enough money to go to college.

On a whim, his first venture into military life comes at age sixteen when he serves for thirteen days in the Connecticut Militia. He then devotes himself to work as a pharmacist and bookseller, earning enough income to repurchase his family homestead. After selling it in 1764, he buys three sailing ships which are soon trading successfully in the West Indies.

But the British Sugar Act of 1764 and the 1765 Stamp Act sharply cut into profits and he protests by joining the “Sons of Liberty” and smuggling goods to avoid the taxes. The Boston Massacre of 1770 pushes him over the edge toward violence, and five years later he is elected Captain in the state militia as the Revolutionary War begins. He leaps into action, joining the Green Mountain Boys and Ethan Allen in the capture of Ft. Ticonderoga, after which the two men publicly quarrel over who deserves more credit for the victory. This need for recognition will run throughout Arnold’s subsequent career.

Still his success at the fort captures the eye of Continental Army Commander, George Washington, who asks Arnold to lead another expedition into Canada. During the failed siege of Quebec City in December 1775, he suffers the first of what will be two serious wounds to his left leg.

After recovery, he returns to action and slows the British advance down Lake Champlain at the battle of Valcour Island in October 1776. But instead of being rewarded, he is passed over in February 1777 when the Continental Congress promotes five men his junior to the rank of Major General. Washington writes him a letter claiming his omission as an oversight. When that doesn’t pan out, he submits his resignation before finally being promoted, but without seniority.

His next clash of egos is with General Horatio Gates, who is convinced throughout the war that he, not Washington, should command the Continental Army. Gates actually serves as Arnold’s friend and patron until becoming bitter foes at the “turning point” Battles of Saratoga. In the opening fight on September 19, Arnold receives hurrahs from his troops for halting British General Burgoyne’s advance at Freeman’s Farm. But in his action report, Gates fails to even mention Arnold’s name. A shouting match follows with Gates stripping Arnold of his command.

Eighteen days later, at the battle of Bemis Heights, Arnold achieves his greatest military victory while suffering a devastating injury. He is leading a heroic charge against a British Redoubt when one musket ball strikes his left ankle while another kills his horse, which falls on him. His troops pull him out and apply a tourniquet to the wound. He refuses to allow an amputation and endures a pain filled recovery which results in a left leg two inches shorter than the right and a lifelong limp. During that time he also learns that Congress has struck a medal to honor “Gates, the Hero of Saratoga.”

In 1778 Washington appoints him Military Commander of Philadelphia. Once there he is smitten by one Peggy Shippen, an eighteen year old beauty who, like her father, is a Loyalist to the crown. Arnold lives extravagantly in the city and works various business deals which find him charged with corruption. He again turns to Washington, writing, Having become a cripple in the service of my country, I little expected to meet ungrateful returns.”

On September 21, 1780 he commits his first act of treason, meeting with British Major John Andre and offering to hand over West Point to General Henry Clinton for L10,000 and a high ranking military commission. This begins regular exchanges with Arnold divulging the size and locations of American troops and depots.

While acquitted of corruption charges by a military tribunal in January 1780, Washington sends a note expressing disappointment over Arnold’s imprudent deals in Philadelphia. Along with Peggy, he is accused of “Tory leanings” and then asked by Congress to repay L1,000 that went missing during his Canada campaign.

With that Arnold resigns his Philadelphia post only to be given command over West Point in August 1780. He prepares documents intended for General Clinton on the capture of the garrison, but then the courier Major Andre is arrested and the plot is revealed. This forces Arnold to board a ship sailing for safety to New York. Washington is astonished by the betrayal and suggests a swap of Arnold for Andre which never happens, and the courier is hanged.

Arnold joins the British Army as a Brigadier, captures Richmond and leads many more successful raids, all the time under Washington’s threat of a summary hanging if captured. On December 17, 1781, two months after the surrender at Yorktown, Arnold sails to London along with Peggy and their second child. Over the next two decades they live between England and New Brunswick and have two more surviving children before he dies in 1801 and she follows in 1804.