Bigot
late 16th century (denoting a superstitious religious hypocrite): from French, of unknown origin.
wiktionary
From French bigot(“a sanctimonious person; a religious hypocrite”), from Middle French bigot, from Old French bigot, of uncertain origin. It is often thought to derive from an Old French derogatory term applied to the religious Normans, said to be known for frequently swearing Middle English bi God(“by God”) (compare Old Englishbī god, Middle High Germanbī got, Middle Dutchbi gode), which in any case is thought to be the origin of the surname Bigott, Bygott. (Compare the French use of "goddamns" to refer to the English in Joan of Arc's time.) Liberman however thinks this has "too strong a taste of a folk etymological guess invented in retrospect" and prefers Grammont et al.'s theory that it derives from Albigot(“ Albigensian heretic”). [1] From meaning someone overly (hypocritically or superstitiously) religious it came to mean someone overly devoted to their own religious opinion, and then to its current sense. [2]
etymonline
bigot (n.)
1590s, "sanctimonious person, religious hypocrite," from French bigot (12c.), which is of unknown origin. Sense extended 1680s to other than religious opinions.
Earliest French use of the word is as the name of a people apparently in southern Gaul, which led to the theory, now considered doubtful on phonetic grounds, that the word comes from Visigothus. The typical use in Old French seems to have been as a derogatory nickname for Normans, leading to another theory (not universally accepted) that traces it to the Normans' (alleged) frequent use of the Germanic oath bi God. OED dismisses in a three-exclamation-mark fury one fanciful version of the "by god" theory as "absurdly incongruous with facts." At the end, not much is left standing except Spanish bigote "mustache," which also has been proposed as the origin of the word, but not explained, so the chief virtue of that theory is the lack of evidence for or against it.
In support of the "by God" theory the surnames Bigott, Bygott are attested in Normandy and in England from the 11c., and French name-etymology sources (such as Dauzat) explain it as a derogatory name applied by the French to the Normans and representing "by god." The English were known as goddamns 200 years later in Joan of Arc's France, and during World War I Americans serving in France were said to be known as les sommobiches (see son of a bitch) for their characteristic oaths. But the sense development in bigot would be difficult to explain. According to Donkin, the modern use first appears in French in 16c. This and the earliest English sense, "religious hypocrite," especially a female one, might have been influenced by or confused with beguine (q.v.) and the words that cluster around it.
