"Can we imagine him (Shakespeare) so utterly ignorant as to make a barbarous negro plead royal birth, -- at a time, too, when negroes were not known except as slaves? . . . Besides, if we could in good earnest believe Shakespeare ignorant of the distinction (between a Moor and a 'negro'), still why should we adopt one disagreeable possibility instead of ten times greater and more pleasing probability? It is a common error to mistake epithets applied to dramatis personae to each other as truly descriptive of what the audience ought to see or know. No doubt Desdemona saw Othello's visage in his mind: yet, as we are constituted, and most surely as an English audience was disposed in the beginning of the seventeenth century, it would be something monstrous to conceive this beautiful Venetian girl falling in love with a veritable negro. It would argue a disproportionateness, a want of balance, in Desdemona, which Shakespeare does not appear to have in the least contemplated."
-- Samuel Taylor Coleridge, "Notes on Some Other Plays of Shakespeare, section IV" (1818)