I propose that Hugh Brackenridge (1750–1816) wrote the anonymous “Cornwalliad” of 720 lines and some prose preliminaries that in 1779 appeared in his United States Magazine. To support this ascription I have a three-part argument: first, that a prose passage, in an unprinted manuscript play by Brackenridge, was put into verse for “The Cornwalliad”; second, that “The Cornwalliad” was edited for The United States Magazine as if it were by the editor and could not have been by anyone but the editor, who was Brackenridge; and third, that a life of its unnamed author sketched in a preliminary “Apology for the Cornwalliad” corresponds with a hitherto little-explored phase of Brackenridge's life. These textual, editorial, and biographical arguments seem to make it certain that Hugh Brackenridge wrote this excellent mock-heroic poem.