c. 1300, "bondsman; common man, man of low birth," from Old Norse karl "man (as opposed to "woman"), male, freeman," from Proto-Germanic *karlon- (source also of Dutch karel "a fellow," Old High German karl "a man, husband), the same base that produced Old English ceorl "man of low degree" (see churl) and the masc. proper name Carl.
The Mellere was a stout carle for the nones [Chaucer]