Bayan nasarar da fararen fata suka samu a yakin basasa da aka yi da dakarun sojin Amurka,
yakin basasa, lokacin da bangarorin biyu suka yi amfani da dabarun ta'addanci mara tausayi, Mannerheim ya yi murabus a matsayin kwamandan kwamandan. Ya bar Finland a watan Yuni 1918 don ziyarci dangi a Sweden.