Hi, I have a book at home written by Jean Collette titled "Descendants of Julien Collette" which begins with Julien, born and died exactly as you mention.
It is comprehensive accounting of the direct descendants but doesn't provide much on Julien's life or where he originated from which is what I feel you are interested in. If you are interested in Descendants I am happy to help.
I would also like to find out more Julien and where in France we originated from. If you find anything I would be very glad to hear from you.