David Steuart Erskine, 11th Earl of Buchan (1742–1829), Scottish author and antiquarian, was born in Edinburgh. After receiving an informal education during his youth, he attended classes at Saint Andrews, Edinburgh, and Glasgow universities, but never received a degree. In 1762 he was commissioned in the British army, rising to the rank of lieutenant before his appointment as secretary to the British legation in Madrid four years later, a post he never assumed. Erskine became the Earl of Buchan in 1767 after the death of his father and immediately began a series of land reforms on his ancestral properties that both helped his tenants and improved his own financial situation. Buchan corresponded frequently with Benjamin Franklin and George Washington, supported the American cause during the Revolutionary War, and also wrote numerous works advocating political reform in Great Britain. He patronized poets and artists, founded the Society of Antiquaries of Scotland in 1780, and was later elected a member of both the American Philosophical and American Antiquarian societies. Buchan died at his family estate of Dryburgh Abbey (ODNB description begins H. C. G. Matthew and Brian Harrison, eds., Oxford Dictionary of National Biography, 2004, 60 vols. description ends ; James Gordon Lamb, “David Steuart Erskine, 11th Earl of Buchan: A Study of his Life and Correspondence” [Ph.D. diss., University of Saint Andrews, 1963]; Leonard W. Labaree and others, eds., The Papers of Benjamin Franklin [1959– ], 21:203, 39:186–7, 346–7; Washington, Papers description begins W. W. Abbot and others, eds., The Papers of George Washington, 1983– , 56 vols.  Colonial Ser., 10 vols.  Confederation Ser., 6 vols.  Pres. Ser., 16 vols.  Retirement Ser., 4 vols.  Rev. War Ser., 20 vols. description ends , Pres. Series, esp. 5:284–5; Harrison Ross Steeves, Learned Societies and English Literary Scholarship [1913], 78–9; APS description begins American Philosophical Society description ends , Minutes, 18 Apr. 1794 [MS in PPAmP]; American Antiquarian Society, Transactions and Collections 9 [1909]: 330; London Standard, 24 Apr. 1829; gravestone inscription at Dryburgh Abbey).

The esteemed letter was TJ to Buchan, 10 July 1803 (PTJ description begins Julian P. Boyd, Charles T. Cullen, John Catanzariti, Barbara B. Oberg, and others, eds., The Papers of Thomas Jefferson, 1950– , 38 vols. description ends , 40:708–10). The commercium epistolicum trans atlanticum was probably Buchan’s personal copy of John Mitchell, The Present State of Great Britain and North America, with regard to Agriculture, Population, Trade, and Manufactures, impartially considered (London, 1767), which is in MHi.

Nicholas P. Trist purchased a portrait of Buchan on behalf of Joseph Coolidge for $8.50 at the January 1827 Monticello estate sale (Bill for Coolidge from Monticello Estate Sale, [after 19 Jan. 1827] [MS in ViU: TJP-JK]). Shortly thereafter, Coolidge wrote from Boston to Trist: “the Earl of Buchan wh. comes next in yr. list, I am indifferent about him, let him go to New York” (Coolidge to Trist, 8 Mar. 1827 [RC in DLC: NPT]).