Changes

|cellpadding=2 cellspacing=1 style="font-size:95%;font:95%"|Post-[[Horus Heresy]] (Loyalist Legions)<br>Some Traitor Legions still active

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The twenty '''Space Marine Legions''', also known as the '''Legiones Astartes''', were created by the [[Emperor of Mankind|Emperor]] to take part in the [[Great Crusade]] in what was later known as the '''First [[Founding]]'''. All the [[Space Marines]] of a Legion ("battle-brothers" amongst themselves) were modified with help of the DNA samples of a single [[Primarch]]. As a Primarch was found, he would receive the [[Legion Master|command]] of his respective Legion.

==History==

===Great Crusade and Horus Heresy===

The Legiones Astartes were originally created by the [[Emperor]] and his gene-wrights in the closing days of the [[Unification Wars]] and the extinction of their predecessors, the [[Thunder Warrior]]s. The new [[Astartes]] had superior lifespans and discipline to those of the Thunder Warriors, and were intended by the Emperor to spearhead his coming [[Great Crusade]].{{Fn|7a}} Each of the twenty Legions were created from [[gene-seed]] derived from a single [[Primarch]], which were themselves maturing deep under the Himalayan Mountains before they were stolen away from the Forces of [[Chaos]].{{Fn|6a}} However, while the Gene-Seed was created by the Emperor, it was perfected and mass-produced by the Gene-Cults of [[Luna]] after they were [[First Pacification of Luna|pacified]] by the early Astartes.{{Fn|18}} The combat debut of the Legiones Astartes occurred towards the end of the [[Unification Wars]] when they fought rebellious [[Thunder Warrior]]s in the [[Palace Coup]].{{Fn|30}}