The infamous Minnesota policeman shares a last name with Nicolas Chauvin, the “legendary, possibly apocryphal” French soldier who inspired the term “chauvinism.” In its turn, the surname Chauvin can be traced back to the French adjective chauve, “bald,” ultimately from Latin calvus.
The theologian and dictator John Calvin wasn’t exactly their namesake but came pretty close: his family name was Cauvin, without the “h” but also meaning “bald.” Apparently, his native Picardian dialect had not yet completed the consonant shift typical of standard French and retained the hard “c” at the beginning of this word.
The ambitious young man soon Latinized his name. As the Reverend Erasmus Middleton explained around 1780:
For as the Picard word Cauve, and the French Chauve, is by all good authors expressed in Latin as Calvus; so Cauvin in Pichard, and Chauvin in French, must in Latin be Calvinus.
And so the theologian’s surname lived on in France as Chauvin while its Latin version, without the ending “us,” became a personal name in Britain and the English-speaking world.