For those of us researching East Prussia, there is a large trove of
records lurking in the ancestry.com databases.
Specifically, the Jewish vital-records cards for Koenigsberg (now
Kaliningrad, Russia) have been put on line and indexed, BUT...
...they're in a collection called "Germany, Lutheran Baptisms,
Marriages, and Burials, 1519-1969".
These records cover well over a century, ending in 1874.
Roger Lustig Princeton, NJ USA research coordinator, GerSIG