Aurora Chapter - Origins: The origins of the Aurora Chapter can be traced back to the Great Crusade over ten millennia earlier, when it was still a part of the Ultramarines Legion, then known as the XIIIth Legion, before their reunification with their Primarch Roboute Guilliman.Following their unification with their primarch, Guilliman quickly set about restructuring his Legion's operational doctrine and hierarchy to suit his personal tastes and style of leadership.While the newly espoused doctrine of structured adaptability became deeply ingrained within many of the Legion's chapters, there were some notable deviations from this pattern. Some few individual chapters, through long held preference or some quirk of supply, maintained notable strengths of non-standard equipment or personnel.One of the more noteworthy examples of this was the 4th Chapter, known within the Legion as the "Aurorans," who operated roughly five times as many armoured vehicles as a standard Legion chapter.Before their unification with their primarch, the warrior brotherhood of the XIIIth had, at that time, only in the solar decades after their initial raising on Terra, begun to display its achievements visually.But rather than take on a particular livery and iconography as a whole, individual companies who had come to prominence in a particularly important Imperial Compliance operation or campaign took on additions to their core Legion livery -- which maintained the post-Unification storm grey and gunmetal they had worn since the retaking of Sedna at the edge of the Sol System at the start of the Great Crusade -- to commemorate their greatest achievements.The principally armoured formations of the XIIIth Legion helped halt an Ork advance on the ash plains of Cypra Mundi, and in doing so had saved a city of millions from a savage death. Afterwards, they commemorated the battle by mirroring on their right pauldron the emerald light of the blazing aurora borealis that had riven the skies under which they had fought. Such honours were claimed as the Legion's strength made visible.Following the end of the Horus Heresy, Roboute Guilliman was responsible for the restructuring of the Imperium's military forces. The vast Space Marine Legions would be broken down into numerous, smaller existing formations, known as a Chapter.When the Second Founding of the Space Marines was decreed seven Terran years after the death of Horus and the end of his Heresy, most of the old Loyalist Legions were divided into fewer than 5 Successor Chapters, but the Ultramarines were divided many times. The existing armoured formations of the Ultramarines 4th Chapter became a part of the newly founded "Aurora" Chapter.Since that bygone era, the Aurora Chapter has always been known as the undisputed masters of armoured assault. They boast more Land Raiders and Predators than many other Space Marine Chapters. Ever since their creation, in the Second Founding, they have preferred massed spearheads led by heavily armoured main battle tanks, earning them renown throughout the Ultima Segmentum.Heeding the summons of Ultramarines Chapter Master Marneus Calgar, the Aurora Chapter recently deployed on the Zeist Campaign in support of the Ultramarines against the emergent Tau Empire.