The Rocky Mount Historic Site (40SL386) in Piney Flats, Tennessee, houses structures that many believe date to the founding of the Tennessee territory, ca. 1770, when settlers from North Carolina and elsewhere traversed the southern Appalachian Mountains to establish new homes along the western frontier. Rocky Mount was purportedly built by William Cobb between 1770 and 1772. We cored logs on the Cobb House and adjacent Dining Room to date the tree rings and determine when these trees were harvested. Our analyses yielded 88 measurement series from 69 logs (45 from the Cobb House and 24 from the Dining Room), 39 of which yielded cutting dates. The Cobb House contained logs cut as early as spring 1826 and as late as 1828, while the Dining Room contained logs cut between 1828 and 1830. We conclude that the Cobb House and adjacent Dining Room were not built by William Cobb between 1770 and 1772 but were instead built between 1826 and 1830 by Michael Massengill, a grandson of William Cobb. Archaeological and architectural analyses performed previously provide corroborating evidence of these later construction dates. Documentary evidence supports the location of land owned by William Cobb south of the Watauga River between Carroll Creek and Knob Creek, just to the west of present-day Johnson City.
The log structures at the Rocky Mount Historic Site (40SL386) in Piney Flats, Tennessee (Figures 1 and 2) play a significant role in the history of Tennessee. The site is located near the original Watauga Settlement near the confluence of the Watauga and Holston Rivers in northeastern Tennessee, where settlers from North Carolina, South Carolina, and Virginia settled in the 1770s attracted by the desirable fertile farmland of eastern Tennessee found along riparian corridors. Purportedly built between 1770 and 1772 by William Cobb (1723-1803), the Cobb House and its adjacent Dining Room represent perhaps the earliest known intact structures in Tennessee. Furthermore, the first governor of the "Territory of the United States South of the River Ohio," William Blount, arrived in the territory after being appointed by President George Washington and governed the territory from the Cobb House between 1790 to 1792. Thus Rocky Mount served as the first capital of what would later become the state of Tennessee (Cobb 1926).
The history of the Rocky Mount site, however, remains clouded in mystery during its earliest decades. William Cobb relocated to Grainger County ca. 1795 and the Rocky Mount site then passed to Henry "Hal" Massengill Jr. (1758-1837), who had married William Cobb's daughter, Penelope (1761-1810) (Edwards 1976; Massengill 1955). Hal Massengill was the son of Henry Massengill, Sr. (1730?-?), who was among the first settlers to arrive in the Watauga River region ca. 1770, and whose family had close ties to the Cobb family (Henry Sr. married Mary Cobb (1735?-?), William's sister). No deed record exists in the Sullivan County Deed Books to verify the transfer of property from William Cobb to Hal and Penelope Massengill, however. Later, Henry Massengill, Sr., sold the Rocky Mount property to Michael Massengill (1792-1856), via deed dated 20 March 1827 (page 322, Sullivan County Deed Book 10) (Massengill 1955: 10). The "Henry Massengill, Sr." here is in fact Hal Massengill, Jr. who "was frequently referred to as Senior after the death of his father" (Massengill 1931:263).
The Cobb House and property remained in possession of four generations of Massengills when, on 15 September 1959, the State of Tennessee purchased Rocky Mount (DeFriece and Williams 1966). Today, the site is managed jointly by the Tennessee Historical Commission and the Rocky Mount Historical Association, and serves as the state's only living history museum.
The primary objective of our research was to clarify the history of site occupation by determining the cutting dates of oak trees used to construct the Cobb House and Dining Room using dendrochronological crossdating techniques that assigned precise calendar years to all tree rings on the sampled logs. …