For Constantine the Great it was 'Sardica mea Roma est' (Serdica is my Rome). He considered making Serdica the capital of the Byzantine Empire instead of Constantinople. which was already not dissimilar to a tetrarchic capital of the Roman Empire. In 343 AD, the Council of Sardica was held in the city, in a church located where the current 6th century Church of Saint Sophia was later built.