Hey /r/thougth,

The French Calvinists as you know were called "Huguenots" and acquired such a nickname during 1558/59. This is a time when Elizabeth became Queen Elizabeth the 1st and when the Catholic monarchs seemed (though it eventually went to shit) to have put aside their differences to become united against protestantism after a peace treaty was signed at Cateau-Cambresis between the kings of France and Spain. Anyway, now that we have that out of the way, the term 'Huguenot' is of uncertain origin. I have read books by Diarmaid MacCullough (famed Reformations scholar) all the way to Bernard Cottret (famed Calvin scholar) and there really isn't a point of discernible origin. What both can agree on is that the term 'huguenot' might have came from the word 'Eidgenossen' or 'Eidguenots' which is a derivation of a German word that means 'associates' or 'confederates'. Well these Eidgenossen/Eidguenots started Geneva's (Geneva being the place where Calvin had his famous ministry and the place that Calvinism had its "base") revolt from Savoy in the 1520s and who provided the conditions for Calvin's organization of the Genevan Reformation (MacCulloch 286, 287)(Cottret 115). Hope that helps!

Sources:

Cottret, Mr. Bernard. Calvin: a Biography. Grand Rapids: Wm. B. Eerdmans Publishing Co., 2000.

MacCulloch, Diarmaid. The Reformation. New York, N.Y.: Penguin Books, 2005.