A churl (etymologically the same name as Charles / Carl and Old High German karal), in its earliest Old English (Anglo-Saxon) meaning, was simply "a man" or more particularly a "husband", but the word soon came to mean "a non-servile peasant", still spelled ?eorl(e), and denoting the lowest rank of freemen. According to the Oxford English Dictionary, it later came to mean the opposite of nobility and royalty, "a common person". Says Chadwick:
This meaning held through the 15th century, but by then the word had taken on negative overtones, meaning "a country person" and then "a low fellow". By the 19th century, a new and pejorative meaning arose, "one inclined to uncivil or loutish behaviour"--hence "churlish" (cf. the pejorative sense of the term boor, whose original meaning of "country person" or "farmer" is preserved in Dutch and Afrikaans boer and German Bauer , although the latter has its own pejorative connotations such as those prompting its use as the name for the chess piece known in English as a pawn; also the word villain--derived from Anglo-French and Old French, originally meaning "farmhand"--has gone through a similar process to reach its present meaning).
The ?eorles of Anglo-Saxon times lived in a largely free society, and one in which their fealty was principally to their king. Their low status is shown by their wer?ild ("man-price"), which, over a large part of England, was fixed at 200 shillings (one-sixth that of a the?n). Agriculture was largely community-based and communal in open-field systems. This freedom was eventually eroded by the increase in power of feudal lords and the manorial system. Some scholars argue, however, that anterior to the encroachment of the manorial system the ?eorles owed various services and rents to local lords and powers.
In the North Germanic (Scandinavian) languages, the word Karl has the same root as churl and meant originally a "free man". As "housecarl", it came back to England. In German, Kerl is used to describe a somewhat rough and common man and is no longer in use as a synonym for a common soldier (die langen Kerls of Frederick the Great of Prussia). Rígsþula, a poem in the Poetic Edda, explains the social classes as originating from the three sons of Ríg: Thrall, Karl and Earl (Þræl, Karl and Jarl). This story has been interpreted in the context of the proposed trifunctional hypothesis of Proto-Indo-European society.
Cognates to the word ceorle are frequently found in place names, throughout the Anglophone world, in towns such as Carlton and Charlton, meaning "the farm of the churls"[dubious ]. Names such as Carl and Charles are derived from cognates of churl or ?eorle.
While the word churl went down in the social scale, the first name derived from the same etymological source ("Karl" in German, "Charles" in French and English, "Carlos" in Spanish etc.) remained prestigious enough to be used frequently by many European royal families - owing originally to the fame of Charlemagne, to which was added that of later illustrious kings and emperors of the same name. Król, the Polish word for "king", is also derived from the same origin.
In most Germanic languages this word did not take on the English meaning of "lowly peasant" and retains its original meaning of "fellow, guy"; cf. West Frisian kearel, archaic tsjerl, tsjirl, Dutch kerel, Low German Kerl (also borrowed into German), Swedish karl, and so on.