This collection consists of records collected and created by the Oscar Mueller family. The records document their professional and personal lives spanning from 1856 to 2017. Oscar Mueller’s papers span from 1864 to 1997 and mainly consist of his activities as a lawyer and an amateur historian. Series include biographical/historical materials, correspondence (incoming, outgoing, general, and miscellaneous), court papers, financial records, legal documents, subject files, and miscellany. Record types include professional correspondence, biographical articles, masonic membership documents, obituaries, certificates and diplomas, court transcripts, financial records of attorney fees, real estate contracts and deeds, and research material files. Josephine Mueller’s papers span from 1890 to 1977 and mainly consist of her activities in community groups and organizations. Series include biographical/historical materials, correspondence (incoming, outgoing, general, and miscellaneous), diaries, legal documents, and miscellany. Record types include family correspondence, masonic membership documents, obituaries, and real estate documents. George Mueller’s papers span from 1861 to 2013 and mainly consist of his correspondence and historical research activities. Series include biographical/historical materials, correspondence (incoming, outgoing, general, and miscellaneous), diaries, employment records, financial records, legal documents, membership records, organizational records, school notes/records, subject files, miscellany, and clippings. Record types include certificates and diplomas, military records, employment applications and qualifications, stocks, educational transcripts, membership and organizational documents for masonic clubs and rotary, and historical research materials. Glenn and Helen Mueller’s records span from 1910 to 2016 and mainly consist of biographical and historical materials. Series include biographical/historical materials, correspondence (incoming and outgoing), diaries, subject files, miscellany, and clippings. Record types include family correspondence, military records, and forestry materials. The Cook Family records span from 1856 to 2017 and mainly consist of genealogical records and family correspondence. Series include biographical/historical materials, correspondence (incoming, outgoing, general, and miscellaneous), diaries, legal documents, miscellany, and clippings. Record types include certificates, family letters, real estate documents, and newspaper clippings. Also included is the correspondence between George and Glenn to their parents during their military service in World War II. Beginning with Glenn in 1942 and ending with George in 1946, the letters detail their experience and activities in the European theater of the war. Countries they were stationed at include England, France, Germany, and on the North African continent.