Charles Washington (May 2, 1738 - September 16, 1799) was the youngest full brother of George Washington. He was born at Hunting Creek, Virginia. Shortly after Charles's birth, his family moved to the Ferry Farm near Fredericksburg, where he spent most of his childhood. He gained prominence in this area, becoming a substantial landholder, a member of the vestry of St. George's Church, and a signer of the Westmoreland Resolutions which opposed the British Stamp Act of 1765. He married Mildred Thornton and had four children: George Augustine, Samuel, Frances, and Mildred Washington.

Charles Washington came to present Jefferson County in 1780, having inherited land from his half-brother, Lawrence. He began construction of his home, Happy Retreat, near the future site of Charles Town, the same year but did not live to see its completion. From Happy Retreat in 1786, he laid out plans for Charles Town to be built on 80 acres of his land. The town square, where the courthouse stands, was deeded by Washington as a gift to the town. The town was incorporated in January 1787. Charles Washington is buried in the family plot at his Jefferson County home.