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.
However in 1527 Norfolk took a mistress, Bess Holland, the daughter of his steward, with whom he lived openly at Kenninghall, and whom the Duchess described variously in her letters as a bawd, a drab, and 'a churl's daughter', 'which was but washer of my nursery eight years'.
Adrian James Martyn has speculated that the original form was huscarl, a compound word of two distinct words in Old English, hus (house) and churl (a peasant.