This event takes place after Suzumiya Haruhi played Warhammer 40K in the SOS-Dan clubhouse, and becomes so inspired by the fiction of the game that a gigantic closed space is created. The entire SOS-Dan is dragged into this closed space, and an entirely new universe is created, destroying the delicate balance between dimensions. Note that this story is meant to be a prologue, and will serve as the basis of all future stories to come.
Multiple anime characters from multiple anime series are involved in this project, but the central figure is still the God-Empress Suzumiya Haruhi, though I believe fans from the anime series that made an appearance here might be interested.
Yes, that is right, this is more like a project rather than just a story. Each Astartes Legion will eventually receive an Index Astartes article describing its origins and attributes. Eventually, rules may be created that will allow actual Warhammer 40K players to field armies from these Astartes Legions on the tabletop game. It's a vast undertaking, and one that I am not confident of completing alone.
As the saying goes, a journey of a thousand miles begins with a single step. So without furthur ado, let us begin:
Prologue Part I
In the 29th Millennium, mankind had become scattered throughout the stars, amongst the great vastness of the galaxy. So many worlds were colonized since the invention of faster-than-light travel that it had become impossible to count or keep track the number of human inhabited worlds in the galaxy. Such travel was made possible by the discovery of the warp, an alternate dimension seething with psychic matter and raw energy. Ships moved quickly between stars by piercing the veil of reality, hurling itself into the warp and back out to normal space at the destination. Though far from completely reliable, the warp proved to be mankind's most convenient way to move and communicate amongst the sea of stars.
Unfortunately for the myriad human colonies, at the start of the 30th Millennium, fierce warp storms engulfed the galaxy, isolating the colonies from each other, their citizens unable to communicate or travel offworld for centuries. Cut off from all form of external influence for generations, the colonized worlds experienced severe civil wars fought by factions who demanded mastery of their respective planets. These wars, combined with rampant alien incursions, tore the colonies apart, causing severe hardship for the general populace. Terra, the homeworld of humanity, was no exception to this rule.
The brutality of the wars fought on Terra easily rivaled the dozens of world wars fought on humanity's cradle throughout the endless centuries. The nations of the world had degenerated into kingdoms ruled by barbarians armed with the best technology of its time. It was in this period that the Empress was first heard of, Her name rising from anonymity to become synonymous with the light of humanity. Utilizing super-advanced genetic technologies and enlisting the best scientists and genologists of the day, the Empress succeeded in creating the most powerful and deadliest warriors that the universe would ever see, the Adeptus Astartes, the Space Marines of the Empress.
History states that the Empress initially led a single legion of Space Marines, bringing them directly under Her command. In order to share the responsibility of planning and persecuting the coming war, the Empress gave appointments to Her group of four companions, who were henceforth known as the Imperial Council. The man known only as Kyon was made overall commander of the Imperial Guard, an organization consisting of regular men and women who fought in the name of the Empress, while Koizumi Itsuki was made the chief of the Empress' Inquisition, a secret institution designed to silently hunt down opposition to the Empress' cause, and gather intelligience for military operations. Asahina Mikuru was made the chief of the Imperial Household and commander of the Empress' personal guard unit, the Adeptus Custodes, while Nagato Yuki became responsible for leading the Imperial Navy of warships.
Thus prepared, the Empress, Her Imperial Council, the fledging Imperial Army and the Astartes Legions went to war, with the aim of the conquest of Terra.
The war, which came to be known as the Reunification Wars, was a spectacular affair. Led personally by the Empress, armored with power armor that were light years ahead of any other personal protection, and armed with Bolters that fired destructive bolts of mass-reactive explosive payloads, the Astartes made short work of Her enemies. The combat prowess of the Space Marines were such that they literally had no equal on the battlefield, each Space Marine an army of one that could easily best a hundred normal soldiers. With such warriors at her beck and call, the Empress easily completed the conquest of Terra within a time period of two years, bringing to heel the kingdoms of the world and uniting them under Her divine leadership. The conquest of Terra, however, was only the beginning of the Empress' plans.
The recruitment and creation of the Astartes had continued at a feverish pace even as the Empress fought the Reunification Wars, with the genetic labs and training facilities in modern Japan creating Astartes as fast as was humanly possible. By the end of the Reunification Wars, there were forty thousand Astartes spread out over twenty Legions. The Empress in Her wisdom, knew that the expansion of the Astartes program was crucial to Her future plans, but She was also aware that it would be impossible for any one person, even Her, to directly control so many Legions of Astartes at once.
And so it was, that at the conclusion of the conquest of Terra, the Empress, accompanied by Her Council, began the search across time, space and dimensions for suitable candidates to lead her Space Marine armies. Slowly and painfully, 20 individuals were found and instated as leaders of their respective Space Marine Legions, while the Legions repaired and rearmed themselves. The genetic material of these individuals would be used in the future creation and training of Astartes for their respective Legions, thus ensuring that a Space Marine Legion would always take after its leader in body and soul, much like how a child takes after its parents.
These leaders became known as Primarchs, a name coined and sanctified by the Empress Herself. The Primarchs would directly command their Legions while the Empress provided overall strategical direction. Unfortunately, some Primarchs were bought into the Empress' service by the force of Her will; a fact that rankled with those bought into submission this way, and which would play a big part in later events. Others served willingly, realizing that the Empress was no mere mortal, but a person of immense power who was worth their loyalty.