 Complete the following phrase:  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 913919. Leo and a younger brother, Romanos, participated in the campaign against Bulgaria that ended in the disastrous 