Some sources report an Anglicisation of her name as being ELIZABETH, but this is following the etymology all the way back to ISABELLE's origins. I have seen Isabelle given more often than Elizabeth.
The Bavarians were (as far as i can tell) German-speaking, although back in 1370 when Isabeau was born, i suspect that the courts were more fluent in French. So we don't know if her given name was Isabeau, or if that is the Gallicisation of her given Germanic name, which could have been either one of the more obviously Elizabeth derived names (ELISA, ELISABETH, LISBETH) or one of the more Isabelle resembling (LIESL, ELSE, etc). I'm sure its been recorded somewhere but so far i haven't been able to lay my own eyes upon it (or a mention thereof).
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So, my learned friends, since we are on the subject: i have been dying to get my hands on a more detailed biography or history of CharlesVI and Isabeau of Bavaria than the brief treatment given them towards the end of "A Distant Mirror" (Barbara Tuchman). Can anyone recommend to me a book that details CharlesVI reign and the activities of Isabeau during this time?? Even if it covers other kingdoms besides France, or time periods bookending their reign. The only 2-3 books i have found so far are in French, and sadly i never studied French. They also seem to be theses and not print books.