Sofoklis Dousmanis was born in Corfu in 1868, a descendant of the Albanian origins Dushmani family, grandson of Antonio Dusmani and brother of Viktor Dousmanis. He graduated from the Hellenic Naval Academy in 1888. He was a very capable officer, with royalist convictions. Ranked Commander, he served as chief of staff (αρχιεπιστολεύς) for the Naval Exercises Squadron in 1910, and as Director of the Administrative Section of the Royal Navy General Staff (Γενικόν Επιτελείον Ναυτικού) in 1912. Upon the outbreak of the First Balkan War in October 1912, he was appointed captain of the fleet's flagship, the new cruiser Georgios Averof, as well as chief of staff for the Aegean Fleet under Rear Admiral Pavlos Kountouriotis. In this capacity he participated in the two victorious naval battles of Ell