I was a doctor turned general, an Irish-born Patriot who fought from the wilderness to Yorktown.

I was born in 1744 in Clyduff, King’s County, Ireland. I studied medicine at Trinity College in Dublin and joined the British Army as a surgeon’s mate in the 18th Royal Irish Regiment of Foot. That post brought me to the American colonies, where I served at Fort Pitt — deep in the rugged frontier of western Pennsylvania. But in 1774, I left the king’s army behind and settled in Lancaster to practice medicine.

When the Revolution broke out, I traded my scalpel for a rifle. I joined the Continental Army and was named a colonel of a Pennsylvania rifle battalion. In 1776, during the New York campaign, I led a small force that stalled a British advance at Throg’s Neck. Just twenty-five of us held back over 4,000 British troops. That delay gave Washington’s army time to reach stronger ground and may well have saved it from collapse.

I rose quickly. Promoted to brigadier general, I returned to the Ohio frontier and took command at Fort Pitt. There, the war looked different — a brutal mix of Loyalist raids and Native resistance. In 1778, I ordered an attack on a Lenape village, believing them to be allied with the British. They weren’t. The attack drove neutral tribes into the fight and complicated the conflict in the west. It was a mistake I carried with me.

In 1781, I was called back east to serve as adjutant general of the Continental Army under Washington. I organized logistics, handled wounded soldiers, and kept the army supplied during the siege at Yorktown. When the war ended, I was promoted to brevet major general and left military service in 1783.

After the war, I returned to Lancaster and served in Congress and as a trustee of the University of Pennsylvania. I lived out the rest of my days quietly and died on September 4, 1802.

Though I trained to heal, war made me a fighter. From Pennsylvania’s woods to Virginia’s victory, I stood with the cause until the final battle was won.