Kammala jumla mai zuwa: 3rd Missouri Infantry Regiment ya yi aiki a cikin Sojojin Tarayyar Amurka a lokacin yakin basasar Amurka. An kaddamar da rundunar sojojin soja a ranar 17 ga Janairu, 1862. Ya yi yaƙi a yakin Pea Ridge a Arkansas a watan Maris kafin a canja shi a fadin kogin Mississippi. Yayin da yake zaune a Koranti, Mississippi, rundunar ta taka rawar gani a yakin Farmington kafin a kwashe garin. A watan Satumba, rukunin ya ga aikin haske a yakin Iuka kafin a yi aiki sosai a lokacin yakin na biyu na Koranti yayin da 'yan kungiyar suka yi kokarin dawo da garin a watan Oktoba. A farkon shekara ta 1863, an tura rundunar zuwa Grand Gulf, Mississippi, don karfafa kariya ga kogin Mississippi a wannan lokaci. A cikin
Yaƙin Grand Gulf a ranar 29 ga Afrilu, ƙungiyar ta taimaka wajen kawar da harin Navy na Union a kan ayyukan tsaro na Confederate. Bayan da wasu bangarori na rundunar sojojin Tarayyar Tennessee suka sauka a karkashin Grand Gulf, rundunar ta yi yaƙi a cikin wani aiki na jinkiri a yakin Port Gibson a ranar 1 ga Mayu.