The Mary Ball Washington Museum and Library is a museum and historical archive in the Northern Neck of The Chesapeake Bay, Virginia, USA. Its purpose is to preserve the history of Lancaster County, Virginia. It opened in 1958 and was named in honor of George Washington's mother, Mary Ball, a Lancaster County, Virginia native and granddaughter of the ca 1653 emigrant, William Ball I.Past curators of the Mary Ball Washington Museum include Thomas M. Thacker, Cathy Currey, Sarah J.