Isabeau

Isabeau is a medieval French elaboration of Isabel, itself a medieval Spanish and Portuguese form of Elisabeth, which traces back through Latin and Greek to the Hebrew name Elisheba, meaning something along the lines of my God is an oath or my God is abundance. The name was in use among French and Flemish nobility during the Middle Ages, most notably borne by Isabeau of Bavaria, the Queen of France as wife of Charles VI in the late fourteenth and early fifteenth centuries. It has remained rare in modern French and has also seen some revival in Dutch-speaking regions. Related forms include Isabel, Isabella, and Elisabeth.