Belvoir was the plantation and estate of colonial Virginia's prominent William Fairfax family. Built with the forced labor of enslaved people, it sat on the west bank of the Potomac River in Fairfax County, Virginia, at the present site of Fort Belvoir. The main house — called Belvoir Manor or Belvoir Mansion — burned in 1783 and was destroyed during the War of 1812. The site has been listed on the National Register of Historic Places since 1973 as "Belvoir Mansion Ruins and the Fairfax Grave."
William Green's 1669 patent for 1,150 acres (4.7 km2) encompassed most of the peninsula between Dogue Creek and Accotink Creek, along the Potomac River. Although this property was sub-divided and sold in the early 18th century, it was reassembled during the 1730s to create the central portion of Col. William Fairfax's 2,200-acre (8.9 km2) plantation of Belvoir Manor.
Fairfax's elegant new home was completed in 1741. Historic documents and archeological artifacts found at Belvoir Manor both attest to the elegant lifestyle enjoyed by the Fairfax family, thanks to their enslavement of others. The mansion was described in a 1774 rental notice as spacious and well-appointed. Its furnishings consisted of "tables, chairs, and every other necessary article...very elegant." The family imported ceramics from Europe and the Orient to grace its tables.
Planters such as William Fairfax comprised a small elite of Fairfax County's population; most of their neighbors were smaller farmers who sometimes barely managed to make a living. The affluence of such planters was based not only on land and imposing buildings, but on the number of people they enslaved. These people are in the records as chattel passed from one generation to another, and as the probable users of the plain unglazed ceramics found in the outbuildings of Belvoir Manor. After William Fairfax's death in 1757, the plantation passed to his eldest son George William Fairfax (1729–87).