
These actions tested Horus' own resources, and exacerbated existing tensions among some of the other Primarchs, especially those who felt slighted by other decisions of the Emperor or had grievances against their brothers.

The Emperor left the Crusade and returned to Terra to continue his top-secret work regarding Imperial access to the Eldar Webway (a trans-dimensional tunnel system), while relegating the overall administration of the Imperium to aĬivilian authority, the Template:Em. More than two standard (Terran) centuries into the Great Crusade, the Emperor made Horus Lupercal, his most trusted and versatile Primarch, Warmaster (commander-in-chief) of his armed forces and overall leader of the Crusade. While the Emperor was overall commander of the Crusade's expeditions to the stars, the Space Marine Legions and the rest of the Imperial military forces eventually came to be led by his genetically-engineered progeny, a group of twenty so-called Template:Em who were in every aspect even mightier than Space Marines. Promoting the notions of Order and Truth from a strictly human perspective as put forth by the Emperor, the Imperium declared the Milky Way to be the exclusive, rightful domain of Humankind, and a part of its Manifest Destiny.


The objective was to unify the millions of human colonies scattered throughout the galaxy under an Template:Em of science and reason, and against religion and superstition – by extension weakening the influence of Chaos on the human race and the race's evolution. After consolidating his rule on Terra (Earth), and genetically engineering Legions of superhuman warriors (the Space Marines) he embarked early in the 31st millennium on a Template:Em. In the developing Warhammer Template:Spaces40,000 back-story, by the 30th Template:Spacesmillennium the Emperor of Mankind, founder and head of the newly constituted Imperium of Man, had become a major proponent of Order in the Milky Way, and one of the most formidable enemies of Chaos and its forces.
