I don't know about Esche in Wisconsin but my grandmother's maiden name is Esche. I have traced her father to Graudenz in Prussia. I have not been able to find his actual birth/christening record but found his name listed in an index. He was illegitamate and had three illegitamate sisters that died as infants. On the birth records for his sisters that I have been able to locate it lists only the mother as Fredericke Esche. I am trying to find any information about her that I can possibly locate - no luck yet. I do think that I have found a possible brother. My grandfather was born in 1872 and died after WWII. I would be interested to know what information you have and from what part of Germany you are researching.