Lydia Barrington Darragh (born 1729, Dublin, Ireland—died December 28, 1789, Philadelphia, Pennsylvania, U.S.) was an American Revolutionary War heroine who is said to have saved General George Washington’s army from a British attack.

Lydia Barrington married William Darragh, a teacher, in 1753. Shortly thereafter she immigrated with her husband to the American colonies, settling in Philadelphia. She worked as a nurse and midwife with considerable skill and success. In a story first published in 1827 and later elaborated upon, she was credited with having saved Washington’s army in the following manner: During the British occupation of Philadelphia, General William Howe had his headquarters opposite the Darragh house. On the night of December 2, 1777, the adjutant general and other officers commandeered one of her rooms for a secret conference, and, listening at the keyhole, she learned of their plan to attack Washington at Whitemarsh, 8 miles (13 km) away, two nights later. On the morning of the day, December 4, she let it be known that she needed flour from the Frankford mill and obtained a pass to leave the city for that purpose. Once away, she made for Whitemarsh. Encountering Colonel Thomas Craig, a friend, on the road, she told him what she had learned and then, securing her flour, hurried home. The British march that night found the Continental army at arms and ready to repel, and Howe was forced to return to Philadelphia. Darragh lived in Philadelphia until her death.