There are entries for a Herman Haack and a Mrs. Hermann Haack in "Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950). I've indexed about 90 entries for the name Haack, and amny other surnames are referenced with these entries.
Then, concerning Hoppe: there are over 200 entries in the growing data file. Neither the newspapers, nor the index is are online.
Indexing Milwaukee's German newspapers continuously since 2007 ... because _someone_ had to do it!
Gary Rebholz, compiler/editor