Rubuta ci gaba ga wannan sakin layi - Mannerheim ya yi aiki a cikin Sojojin Rasha na Imperial, ya tashi zuwa 1917 zuwa matsayin Lieutenant general. 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 pro-Bolshevik "Reds" da "Whites", waɗanda suke sojojin Majalisar Dattawan Finland, da sojojin Daular Jamus suka goyi bayan su. 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 da Soviet ta mamaye 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.