I believe that I have your connection. I have Julius Stavenhagen, son of Julius Stavenhagen and Mary Glennan of Plymouth, England. I have extensive information regarding this family. The family in Germany was involved in the wool trade as were members of the family as they dispersed around the world. Would love to share information.
P.S. I'm kind of the family historian in the United States (mostly because I've been in contact with family in Europe and keep the family informed at bi-annual family reunions).