Henry Wadsworth Longfellow was an American poet.
The Sixth Doctor mentioned him just by surname and defined him a "primitive American versemaker", after having declaimed verses from his 1841 published work Excelsior while on the asteroid Titan III. (TV: The Twin Dilemma)
The shades of night were falling fast, as through an alpine village passed, a youth, who bore midst snow and ice, a banner with a strange device.