Editing Alternate Heresy (section)

===Warhammer 40K: Legiones Astartes===
[[Armageddon|On the eve of Mankind's greatest victory, with near total domination of the stars,]] the greatest of the Imperium's commanders and most favoured son of the Emperor - [[Horus|Horus Lupercal - Primarch of the Sons of Horus and Warmaster of the Imperium's vast armies]], turned against the light of the Emperor. Convinced by [[ Chaos Gods|the dark whispers of the Chaos Gods]], he led a galaxy-wide [[Horus Heresy|rebellion against the Imperium, splitting the domain of mankind in twain.]] For nine brutal years, the loyal servants of the Emperor fought against their traitorous brothers in a war of almost apocalyptic nature.

Eventually, the Traitor Legions managed to make their way to the capital of the Imperium, to the Throneworld itself - Terra - birthplace of Humanity. In the ensuing battle, countless billions gave their lives in defence of the Emperor of Mankind. The servants of the Dark Gods ravaged and burned the planet, leaving it a husk of its former self. In the aftermath of this apocalyptic battle, Horus lay dead, his very soul destroyed by the psychic might of the Emperor, and the traitors' forces were broken and fled. Losses on the Loyalist side were just as grievous, the Primarch of the Blood Angels, Sanguinius, lay dead, and worst of all, [[The God-Emperor of Mankind|the Emperor Himself had been mortally wounded by Horus in the final moments of the battle]], forcing him to be interred in the Golden Throne.

[[High Lords of Terra|To rule in the Emperor's stead, the leaders of the major branches of the Imperium were brought together in a great council, from which they would forevermore dictate the rulership over the Imperium.]] Their first act was one of monumental importance, and consequence. The Great Crusade was to be renewed whilst the Imperium rebuilt, as the enemies of Mankind could be given no time to rest. The Horus Heresy had kept Mankind from its manifest destiny long enough, and they would not stand idly by. Whilst the this new 'Second Great Crusade' began, an important factor, once a common sight on the battlefield, was missing. [[Space Marines|The Legiones Astartes]] had been nearly shattered by the Heresy - [[Heresy|half their number had turned traitor]] - whilst the loyalists took massive casualties.

[[Rogal Dorn|The Praetorian of Terra, Rogal Dorn]], proposed that the Imperium should not only seek to rebuild the Legiones Astartes numbers, but to eventually expand them even further, [[Space Marine Chapter|by creating new Legions]]. To help guide these future Legions, they would fall back on the wise tenets of the Principia Belicosa, with additional wisdom added to it by Dorn himself. With the death of the strategically brilliant strategist and organiser [[Roboute Guilliman]] at the hands of [[Alpha Legion|Alpha Legion assassins]], Guilliman's proposed treatise, the [[Codex Astartes|Codex Astartes was never completed]], and therefore, never adopted. Thus, the dissolution of the Space Marine Legions into separate Chapters never occurred. Soon, the old Legions were rebuilt and returned to the field of battle, joined by brothers of a new generation, seeking to prove themselves in a new war against the Emperor's enemies.

Unfortunately, without the Emperor's guidance and leadership for the last ten millennia, the Second Great Crusade has suffered immensely. The High Lords and their appointed commanders remain unable to counter the threats that lurk in the darkest corners of the galaxy. Billions are slaughtered every day - victims of poorly planned assaults and ill-prepared defences on planetary scales. In this time of everlasting war, there is only one stalwart force keeping the flame of humanity burning - the Legiones Astartes.

More information in the [https://wh40khomebrew.fandom.com/wiki/Warhammer_40,000:_Legiones_Astartes WH40K homebrew] wiki and in the [https://wh40kfanon.fandom.com/wiki/Warhammer_40,000:_Legiones_Astartes WH40K Fanon] wiki


'''IMPORTANT NOTE: Do not confuse this AU with [[#Successor Legions|Successor Legions.]]'''