History about Warhammer 40K

The primarchs were the 20 genetically-engineered transhuman "sons" of the Emperor of Mankind created in the late 30th Millennium. They were intended to be the immortal and superhuman generals and proconsuls who would command the Emperor's Great Crusade to reunite the scattered Human race beneath His leadership. Their genomes later served as the genetic templates from which the Emperor crafted His 20 Space Marine Legions.

The primarchs were bred to be perfect generals, warriors and statesmen; larger, stronger, faster, and smarter than any normal Human could ever hope to be. They possessed a potent charisma and martial prowess that made them like the mythical gods of old, untouchable by disease, old age or supposedly the petty failings of lesser men.

Each embodied an aspect of war; one was the greatest strategist ever known, another the personification of the terror of war, a third the master of psychic powers, a fourth the greatest practitioner of the arts of fortification, and so on. The primarchs were the Emperor's answer to reclaiming all the lost worlds of Mankind, and welcoming them into His new Imperium.

The Emperor intended to raise His sons to be the best military commanders and political leaders in Human history. They would bring the Imperial Truth to the rest of the Human-settled galaxy in their father's name, serving as His generals and proconsuls.

But the Chaos Gods intervened to foil their great adversary's plans and the primarchs were sprited away through the Warp to other Human-settled planets of the galaxy. Deprived of the Emperor's care and guidance, each developed a personality uniquely shaped -- and sometimes damaged -- by the difficult circumstances of their homeworlds.

Yet for all their gifts, the primarchs were still only men, and in the end their all-too-Human flaws would become the primary obstacle to the realisation of the Emperor's great dream for Mankind.