The space ruled by the Imperium is divided into five fleet zones known as the Segmentae Majoris. The galaxy is such a vast place that it would be unmanageable without this system.
Each Segmentum has its own Imperial Navy and Merchant Fleets, as well as a Segmentum Fortress or Segmentum Naval Base that forms the base of fleet operations within the Segmentum. The Segmentum fleet commanders are known as the Lord High Admirals. The Segmentum Fortress is controlled directly by a high-ranking official of the Administratum known as the Master of the Segmentum.
The Segmentae Majoris and their fortresses are:
|Segmentum Obscurus||North||Cypra Mundi|
|Ultima Segmentum||East||Kar Duniash|