Actually, have just finally found them in Chicago, and looking over my data, yes, they come from Wisconsin about 1860-1880. A family name (first) seems to be VALENTIN or VALENTINE. I have Valentine C BRAHM born 1861Wisconsin , and I recall seeing Wisconsin censuses prior to Chicago, with him in it. He married into my SCHMITT line and related to my CREIGHTON line, both of Chicago, so thought I'd offer info any BRAHM researcher would like.
Anne