What little I've got so far: My father in law is Julius Lange (1934-). His parents were Karl Lange (1893-1968) and Alice Edith Feier (1907-1987). Karl's parent's were Julius Adolph Lange and Mathilda Klukow, although I've got no dates for either of them. Karl & Alice immigrated to the US in the 1950 ...

I'm am trying to help my wife research her father's line, which comes from Łódź. They were ethnic Germans involved in the textile industry, and were a reasonably prominent family. (For example, this was the family house.) Does anyone have any ideas of where I should start looking?

Regards,
Chris