In the old Mennonite Danzig church records, there are some Hieberts dating back to the 1660's. No definite connection between your Claas Hiebert and them has been made. I have come across your Claas Hiebert in my search for the parents of my Claas Hiebert, born 1803 in West Prussia, and died 1876 enroute to America. I once saw a book entitled "The Muensterberg Hieberts" or "The Muensterberg Hueberts". This contains many descendants of your Claas.