I'm not sure what the Wisconsin connection is for this thread, but there are two Rathjen entries in the local index of Milwaukee's German Newspapers:
Wilhelm Rathjen, d. 1873, 7 yrs old, drowned
William R. Rathjen, d. 1917 family death notices
"Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950).
Gary Rebholz, compiler/editor, Milwaukee Wis.
Indexing Milwaukee's German newspapers continuously since 2007...