Coronid Reach

The Coronid Reach is a region of space situated at the borders of the Segmentum Obscurus and the Ultima Segmentum. Located to the galactic North-East of the populous worlds of the Manachean Commonwealth, the Coronid Reach is delimited to the West by the forbidden Coronid Prohibition Zone and to the East by the desolate wilderness known as the Frost Gyre. It is rightly regarded as the furthest anchor point of Imperial civilization and the very edge of Imperial territory before the dark frontier of galactic space. With the populous worlds of the Cyclops Cluster and the Manachean Commonwealth as well as the more baleful Grail Abyss and Cyclothrathine Holdfast, the Coronid Reach is the last region to make up the Coronid Deeps or Coronid Thule, sometimes also known as the Thule-Sector which has ceased to exist.

History
The Coronid Reach is a vast realm that constitutes the northern Frontier of the Imperium. Although counted as an independent division of such neighboring realms such as the Manachean Commonwealth it has no true administrative capital, the entire Reach being somehow overshadowed by the influence of the principal power in this region, the Agathean Domain. Therefor the history of the Coronid Reach pretty much confuses itself with the history of the 60th Expeditionary Fleet and the conquest of Agathon, although the first world to have been colonized was in fact the later Agri-World of Numinal. Perched in by two hostile regions of space, human civilization expanded along the stable warp-routes that originated at Numinal before spreading to the rest of the Reach. The isolation of the worlds of the Coronid Reach would both prove a boon and a curse as during the dark days of the Horus Heresy the entire region was entirely cut-off from other imperial territories and was subjected to the baleful intentions of the Traitor Forge-World of Cyclothrathe. However the Reach’s isolation would also safeguard it from the Warmaster’s direct intentions, leaving only vassal or second-line forces to threaten them. In the first years of the galactic civil war resistance would be fierce, particular in the Agathon Domain which was already at that time the major military and political power of the region.