Otto, basarake Bavaria, ya yi sarauta a matsayin Sarkin Girka tun daga kafuwar sarauta a ranar 27 ga Mayu 1832, a ƙarƙashin yarjejeniyar London, har zuwa lokacin da aka hambarar da shi a ranar 23 ga Oktoba 1862. Ɗan sarki Ludwig I na Bavaria na biyu, Otto ya hau gadon sarauta. sabuwar sarautar Girka da aka kafa yana ɗan shekara 17. Tun farko an gudanar da gwamnatinsa a ƙarƙashin majalisar wakilai uku da ta ƙunshi jami'an kotunan Bavaria.Bayan da ya kai rinjaye, Otto ya cire masu mulki lokacin da suka nuna rashin amincewa da mutane, kuma ya yi mulki a matsayin cikakken sarki.Daga ƙarshe dai buƙatun da talakawansa suka yi na kafa tsarin mulki sun yi yawa, kuma a cikin fuskantar tawaye masu dauke da makamai (amma marasa jini), Otto ya ba da kundin tsarin mulki a shekara ta 1843.A tsawon mulkinsa Otto ya kasa magance talaucin Girka da kuma hana tsoma bakin tattalin arziki daga waje.Siyasar Girka a wannan zamani ta ginu ne bisa alaka da manyan kasashe uku da suka tabbatar wa Girka yancin kai, wato Birtaniya, Faransa da kuma Rasha, kuma ikon Otto na ci gaba da goyon bayan manyan kasashen duniya shi ne mabudin ci gaba da mulki.Domin ya kasance mai ƙarfi, Otto dole ne ya buga muradun kowane mabiyin Girika na Manyan Ƙwararru a kan sauran, yayin da ba ya harzuka Manyan Ƙungiyoyin.Lokacin da sojojin ruwa na Burtaniya suka kame Girka a cikin 1850 da kuma a cikin 1854, don dakatar da Girka daga kai hari kan Daular Ottoman a lokacin Yaƙin Crimean , matsayin Otto a tsakanin Helenawa ya sha wahala.A sakamakon haka, an yi yunkurin kashe Sarauniya Amalia, kuma a karshe a cikin 1862 an kori Otto yayin da yake cikin karkara.Ya mutu a gudun hijira a Bavaria a 1867.