This much-altered frame house just north of the town center was one of the first Georgianstyle buildings erected in Sussex County; in the nineteenth century it received a Greek Revival portico. The dwelling was built for James Mitchell, whose son Nathaniel inherited it. Nathaniel was a prisoner of war in the American Revolution, a member of the Continental Congress, and finally governor (1805–1808). Homes of downstate governors survive in disproportionate numbers: of the eight men who served in 1797–1817 (all from Kent or Sussex counties), houses are still extant for seven. In addition to Rosemont, they are: Daniel Rodgers, Causey Mansion (KT38); Richard Bassett and James Sykes, homes on the Green, Dover; David Hall, 107 Kings Highway, Lewes; George Truitt, house on DE 33 outside Felton; and Daniel Rodney, 231 2nd Street, Lewes.