The Horus Heresy

The Great Heresy War, often poetically known as the "Age of Darkness", was a conflict of galactic proportions that blighted the planets controlled by Mankind for 9 Terran years. When it suddenly exploded across the stars, it marked a turning point for the Emperor of Mankind's campaign to unify the colonies of the Milky Way and instead heralded the Imperium as it stands today. The Horus Heresy is, in a sense, the origin of the Imperium of Man.


The fall of the Imperium began when the Ruinous Powers of Chaos corrupted Warmaster Horus Lupercal, Primarch of the Sons of Horus and beloved son of the Emperor. The Chaos Gods nurtured his ambition and resentment until he betrayed his father and sought dominion over the Imperium.


The death of Horus, the traitorous Warmaster, marked the end of the Heresy; the Emperor was interred in the Golden Throne and the Traitor Legions exiled into the Eye of Terr