Pothos and Leo both followed military careers. According to Constantine VII Porphyrogennetos, already in 911, Leo, despite his youth, became military governor ("strategos") of the theme of Sebasteia, with the rank of "protospatharios". Both brothers played a distinguished role during the regency of Empress Zoe Karbonopsina (913–919). Leo and a younger brother, Romanos, participated in the campaign against Bulgaria that ended in the disastrous Battle of Achelous on 20 August 917.