The Five Hundred Worlds Ultramar

The Five Hundred Worlds of Ultramar are a realm of star systems in the Ultima Segmentum, governed by Guilliman within the Imperium of Man. The realm is a civilised group of systems rather than a single planet. This map classes it as a sector beneath the merged Ultima parent; the separately researched Ultramar Sub-sector entry already holds the administrative cube.

Macragge, Calth, Konor, Iax and Espandor lie within the same civil arrangement, which rests on Tetrarchs, auxilia and a defence fleet rather than on a single fortress-monastery. The realm grew during the Great Crusade, was nearly severed by the Shadow Crusade and the Ruinstorm, and was tested in the Plague Wars, when it became a question whether the resurrected primarch could still govern.

Ultramar retains its standing as the named Five Hundred rather than an arbitrary cluster of hive worlds. Unofficial summaries on this site keep the existing parent, do not treat this entry as Macragge itself, and leave ultramar-subsector as the sibling cube.