Ka kammala wannan jumla: Mannerheim ya yi aiki a rundunar sojojin Rasha, ya zama babban hafsan soji a shekara ta 1917. Yana da babban matsayi a cikin bukukuwan nadin sarautar Tsar Nicholas II a 1896 kuma daga baya ya yi ganawa da Tsar da yawa. Bayan juyin juya halin Bolshevik na Nuwamba 1917 a Rasha, Finland ta ayyana 'yancin kai <unk> amma ba da daɗewa ba ya shiga cikin yakin basasa tsakanin masu goyon bayan Bolshevik "Reds" da "Whites", waɗanda suke sojojin Majalisar Dattawa ta Finland, waɗanda sojojin Daular Jamus suka goyi baya. An nada Mannerheim a matsayin shugaban sojoji na fararen fata, ta hanyar wakilai na Finnish. An nada Mannerheim a matsayin Babban Kwamandan Sojojin kasar a shekarar 1939 bayan
Rashin nasarar mamayewar Soviet na Finland. Ya kuma shiga cikin shirin Operation Barbarossa da kansa kuma ya jagoranci Sojojin Tsaro na Finnish a cikin mamayewar USSR tare da Nazi Jamus da aka sani da Yaƙin Ci gaba. A cikin 1944, lokacin da hangen nesa na rashin nasarar Jamus a Yaƙin Duniya na II ya bayyana, Majalisar Finland ta nada Mannerheim a matsayin Shugaban Finland, kuma ya kula da tattaunawar zaman lafiya da Tarayyar Soviet da Burtaniya. Ya yi murabus daga shugabancin a 1946 kuma ya mutu a 1951.