Overview
Ultramar’s worlds can coordinate supplies and defence across several systems. A settlement in need has a better prospect of an answer than many places elsewhere in the Imperium. There are authorities able to decide what can be spared, and institutions that may still exist when the assistance arrives.
The realm pays for that order through sustained work and military readiness. Its enemies know what is being preserved. When invasion comes, the damage extends beyond a planet’s walls to the arrangements that kept other worlds supplied. This marker represents the stellar realm, with an approximate boundary rather than the orbit of a single inhabited world.
M41 and M42 status
Stellar realm of ordered Imperial worlds.
Guilliman's restored Five Hundred Worlds; a Sanctus bastion held through the Plague Wars.
Timeline
Realm-wide audits coordinate naval, civil, and chapter-linked defenses.
Regional governors increase reserve stores for eastern incursions.
Rift disruption tests the realm's ability to coordinate under stress.
Indomitus authorities use Ultramar as a model for restored order.
The Plague Wars: Mortarion's Death Guard and Ku'gath's plague legions invade Ultramar, fought to a standstill after Guilliman returns from the Battle of Raukos.
Explore the surrounding galaxy
Cartographic positions and several administrative details are intentionally approximate where published Warhammer sources conflict or provide no canonical coordinate system.