I think mine lived there in the 1700/1800s. You need to read Helen Epstein's book :
WHERE SHE CAME FROMA--all about Kolin and my Sachsel family from Kolin.
Susan Fisher Boyer
susiestree@aol.com
Ok. First step is to revert their names to what they probably were in 1800 when they picked them. Jacker is Americanized from Yache or something. Bogen might be ok with the Katzenellenbogen as a reference naming in Jewish history.
Second is to do a name search on Geni. Start with Jacker. Get 84 names, including the ones you put in already. Then search Yacher and other variants. 43 people. etc.
Third is to add these people to a town, hopefully Kolin, but any town that is documented in their profiles. Help others in the process.
I just did Rozenbaum, 1800 profiles, added many to Jewish Town Projects, and sent many requests to add. Helping an American Rosenbaum find his roots.
Go to JewishGen Family Finder for Kolin, look at the names you are interested in, but message ALL the searchers, Find some of them on Geni, add them to the Kolin project. Most JGFF researchers do not know about the Town Projects. It was a small town, every boy married the girl down the street so all are related.
Have fun, it's a hobby.
Dan