Peter, I have a SACK family line that was from Germany. There is a SACK Family Foundation there now. It has been collecting family information for over 200 years. The first edition of what is called the "Silver Book" was dated 1886; second 1900; third 1926; and the fourth was in 1980 with a supplement in 1995. If you get back to me by email, I will try to help. I'm a 6th generation Texan so do not expect much help on information about Germany.