AftermathĪlthough the Heresy campaign lasted less than a standard decade, it was devastating in its scale, and the Imperium's victory came at great cost. The so-called Template:Italic and the whole Horus Heresy campaign, was effectively over. The death of Horus led to disarray among the invading Traitors, whose campaign was by that time also threatened by imminent Loyalist reinforcements, and they hastily retreated. Horus was finally killed in single combat with his creator, while the Emperor himself was nearly fatally wounded in the same action. Following this action, the bulk of rebel forces made their way to the Sol ( Solar) System after a brutal in-system space battle, they managed to make planetfall on Terra and to lay siege to the Imperial Palace. The next stage, expertly directed by Horus and his staff, involved the massacre of three Loyalist Legions that were sent by the Imperium (along with other Legions that had secretly turned Traitor) to crush the rebellion. Inadequate communications and poor intelligence, its leaders stunned or in denial when faced with the enormity of events. During the opening stage of the campaign, the Imperial side is shown to have been beset by Then, in the first open move of the Heresy campaign, he succeeded in culling from the ranks of the rebels those individual units and persons that were still loyal to the Emperor. Horus engaged in subterfuge and secretly contravened Imperial orders, or issued orders designed to weaken and disperse the Loyalist forces, while simultaneously building covert alliances. Most of those who turned against the Emperor became, or already were, corrupted by Chaos. He ultimately lead eight other Primarchs, as well as their Legions and other forces, in war against the Imperium the "betrayal" and campaign became known as the Template:Em. He turned against the Emperor, becoming Template:Em Traitor from the perspective of the Imperium. It involved his near-fatal injury and supposed healing both events were designed to make Horus susceptible to the influence of Chaos and lead to his eventual corruption. Horus became the target of a conspiracy planned by the Chaos gods and executed by their allies and minions. 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.