Similar to the famous "Who is Who", the prosopography of the Central Byzantine period (PmbZ) for the years 641 to 1025 covers all important persons of the Byzantine Empire, such as emperors and empresses, patriarchs etc., in short Byzantines with money, power and influence from the capital Constantinople and the provinces, but also from the surrounding medieval world of states. Unlike a modern "Who is Who", however, the PmbZ also takes into account the ordinary people: monks and nuns, craftsmen, mothers and children, farmers and soldiers. By showing the relationships between individuals and groups, the prosopography not only provides a lively picture of historical events and developments, but also offers a vivid impression of the everyday life of the Byzantines.
The prosopographic research is based on a long tradition dating back to Theodor Mommsen and Adolf von Harnack. In this respect, the prosopography of the Middle Byzantine period is also one of the Academy's traditional projects, even if it is itself of more recent date. Taking secondary literature into account, "biographies" are compiled as precisely and briefly as possible. Also included is all information relating to property and assets, intellectual and literary activity and links to the various social groups in the Empire, especially in the cities. In this way, the encyclopaedia mainly covers the socio-political ruling classes of the Empire.