Smithfield Plantation is the historic home of the Preston family, one of the founding families of Blacksburg and Montgomery County, Virginia. It was built by William Preston (1729-83), who emigrated from northern Ireland with his family in 1737. He married Susanna Smith in 1761 and settled at Greenfield in Botetourt County in 1769. Preston established himself as a leader in the Virginia frontier by serving in the militia in the French and Indian and Revolutionary wars, in the House of Burgesses representing Augusta County from 1766 to 1768 and Botetourt County in 1769, and as County Lieutenant of Fincastle and Montgomery. He was appointed surveyor of Fincastle County in 1772 and moved his family to that area. He built Smithfield, named in honor of his wife, in 1773. Smithfield was the birthplace and home of three Virginia governors, including James Patton Preston (son of William), and John Buchanan Floyd and John Floyd, Jr. (grandsons of William).

Smithfield Plantation remained in the family for generations and is currently maintained by the Montgomery County branch of the Association for the Preservation of Virginia Antiquities. Greenfield was a home in Botetourt County where William and Susanna Smith Preston resided in the 1760s.

See also the detailed list of correspondents in the collection, with some biographical information.

For more information about the Preston family, see John Frederick Dorman, The Prestons of Smithfield and Greenfield in Virginia (Filson Club, Inc.; Louisville, Kentucky, 1982).