Medrengard

Medrengard is a daemon world in the Eye of Terror, the fortress-planet of the primarch Perturabo and the principal base of the Iron Warriors Traitor Legion. It lies beneath a black star that absorbs light rather than giving it, and the whole planet has been remade as a single vast fortification. Its importance in the galactic story is that of a centre of power in the Eye for the Legion that, by its own reckoning, was the one best fitted to besiege a world and the one most poorly rewarded for doing so.

The world is organised around the labour of the Warsmiths, the Iron Warriors’ senior battlefield commanders, who raise spires of kilometre scale that also serve as docks for the warfleets of the Legion. Slaves die in the foundries of Pyriphon, which supply the Legion with weapons and siege engines. Perturabo himself occupies the Kolasikon, a fortress-palace that stands on an island of onyx in a lake of lava. The planet is held by the Iron Warriors alone, and no other Traitor Legion is recorded as having a claim on it.

Medrengard belongs to the period after the Horus Heresy, when the Iron Warriors, who had served Horus at the Siege of Terra, withdrew into the Eye of Terror with the other Traitor Legions. Perturabo’s bitter dealings with his fellow primarchs, among them Fulgrim and Angron, and with the Emperor’s legacy, shaped the character of the Legion that came to be based here. Accounts of how Medrengard was first taken and transformed differ, and the Legion’s own tradition is not a neutral record. Its later development as a daemon world is recorded as a consequence of prolonged exposure to the warp.

The Iron Warriors have fought one another on Medrengard as often as they have fought any other opponent. Rival Warsmiths contend for standing under Perturabo, and warbands that leave the planet to raid the Imperium’s frontiers return to find that the hierarchy of the fortress has shifted. Medrengard is therefore a site of internal conflict within the Legion as much as a base for war against external enemies. On the Orrery map it should be read alongside the Eye of Terror, the Iron Warriors and Perturabo, and on the timeline it is bound to the Legion’s exile after the Siege of Terra and to the continuing Black Crusades, in which Iron Warriors warbands are recorded as taking part. Its present status is that of an occupied, heavily fortified stronghold under Perturabo, whose rule in the Kolasikon is the fixed point of the Legion’s politics.

During his Death Oath exile after the Battle of Tarsis Ultra, the Omphalos Daemonium brought Uriel Ventris to Medrengard, where he turned the Unfleshed against the fortress of Khalan-Ghol and left with them aboard the daemon engine.