I checked my own name database where I have a category for "family name as given name" and note also the language of origin. If I intersect the category with "Old High
German" as origin, I get exactly one name:
Luther.
But anyway, that would not count here, because it is from a
German family name alright, but not in use in Germany itself...
On the other hand, if I do the same for Old English as language of origin, I get over 100 names.
Rene www.AboutNames.ch