Imvrassian Praetorian Prefecture

The Praetorian Prefecture, was the largest administrative division of the Empire.
This administrative division has got the same name as well as of the Roman Empire which originated in the reign of Emperor Constantine I (r.306-337).
A Praetorian Prefecture was created according to geographical or political criteria and the Crown could appoint a Praetorian Prefect to each of them with the rank of Sebastokrator or Sebastokrateira (for the members of the Imperial House) or a citizen with the title of Magistros or Pansebaste.
The Praetorian Prefect's assistants and deputies had the office of Chartoularios.