Dark Eagles Chapter

Dark Hands Chapter

Doom Warriors Chapter

Heralds of Ultramar

Red Hunters Chapter

Revilers Chapter

In the wake of the Horus Heresy the newly formed ruling council of the Imperium, the High Lords of Terra, set about rebuilding and repairing the damage wrought during this terrible civil war. In most need of reorganising and restructuring were the devastated Space Marine Legions as these great armies had borne the brunt of the treachery done by the Warmaster Horus and his traitors. The High Lords tasked the Ultramarines Primarch Roboute Guilliman with the job of reordering the Imperial military forces. His first duty was to revise the organisation of the Space Marines and to codify their institutions, doctrines and armorials. His conclusions became the almost mythic book known as the Codex Astartes, a work so important its contents still form the basis of Space Marine organisation and tactics ten thousand years after it was originally compiled.

The original twenty Space Marine Legions were vast armies numbering thousands of warriors amongst their ranks. During the Horus Heresy this was both a great blessing and a great curse when half of their commanders were corrupted by Horus and threw themselves and their warriors behind his unholy insurrection. The ensuing civil war that erupted between these titanic forces nearly destroyed the Imperium. After the traitors of Horus and been defeated and banished the High Lords of Terra decreed that never again should so many Space Marines fall under the sway of one man, however noble his intent. Thus it was that Roboute embarked on the creation of the Space Marine Chapter. The exact means and timescale of his efforts are lost to memory or record, the result however was that each of the Legions was split into a number of Chapters of roughly a thousand fighting Marines. There is some debate among scholars as to whether the older Legions were already subdivided into Chapters but there is no record of this prior to their reorganisation.

As the old Legions were divided into new Chapters they each adopted new names, badges and colours with only one of the new Chapters retaining the old Legion name and iconography. This was known as the Second Founding of Space Marines. It is not known exactly how many Chapters were created at this time as the Imperial records are incomplete or vague. Most of the new Chapters were derived from the Ultramarines Legion, presumably because it was the largest of the loyal Legions. The Apocrypha of Skaros records that twenty three Chapters were created from the Ultramarines Legion but does not name them. There have been further foundings since then so that by the 41st Millennium there are reputed to be a thousand or more Chapters of Space Marines.

The vast majority of the newly created Chapters took up the Codex Astartes and its doctrines as their guiding law. These Chapters were and are still known as the Codex Chapters. They pride themselves on following the ancient text and applying its principles of warcraft and devotion to the Emperor. In the 41st Millennium there are relatively few of the original Codex Chapters surviving as they have been either destroyed in battle or disbanded. Through the ages other Chapters have developed organisations and heraldries that are so variant with the Codex that they can no longer be considered as such. In truth most Chapters retain the basic organisation and markings or something close to the original though only a few can claim to be Codex Chapters.

Every Space Marine Chapter has a unique basic heraldry consisting of a specific colour or colour scheme and an icon or badge. The Chapter badge is always prominently displayed on the Marines' armour, banners and war machines. The heraldries of the Space Marine Chapters are bold and striking, more akin to a medieval knight's costume than to a uniformed soldier. This is quite deliberate as the Space Marines have little need or desire to disguise their presence on the field of battle. In fact they wish their foes to know that it is Space Marines they face and to be suitably cowed. In addition they are justly proud of their Chapter's heritage and of the honours it has won in battle.

Roboute Guilliman's greatest work describes and prescribes how the entire Imperial military should be organised and how it should fight. Within its hallowed pages are long treatises on all manner of tactics and strategies for virtually all of the soldiers, warriors and war machines known to the Imperium. Of special interest is the volume devoted to the Space Marines. This volume sets out how a Chapter should be structured, recruit, train, fight and dress. In fact every aspect of being a Space Marine is covered in some detail.

The original Codex was compiled approximately ten thousand years ago in the aftermath of the Horus Heresy. It is not known what form the original took: it may have been a manuscript or it may have been a compilation of holo-files or even some combination. Of course manuscript copies were made and distributed. The oldest surviving copy of the Codex is reputed to be the Apocrypha of Skaros. The Liber Arcanum of Grand Marshall Tolof and the Holo-Record 442/33508; Gant Manuscript v2 of the Ceris Archive have some claim to this honour as well. Over the millennia the copies have been copied and recopied many times in order to preserve them. Inevitably, mistakes occur and so it is unlikely that any two copies of the Codex will be identical. Furthermore, the work is constantly being reanalysed and reinterpreted. The original prose style of Roboute is at best archaic and in some cases almost unintelligible. This has led to many varied interpretations over the centuries and to many situations where two entirely different doctrines have been legitimately claimed as 'official Codex' at the same time.

The Primogenitors are the Chapters created from the old Ultramarines Legion during the Second Founding. There are conflicting records as to exactly how many Primogenitor or 'First Born' Chapters were created at this time. However all of these Chapters venerate Roboute Guilliman, the Primarch of the Ultramarines, and their own founding father and patron. All of them are also strict adherents of the Codex Astartes.

Known Primogenitor Chapters are: Eagle Warriors, Silver Eagles, Doom Eagles, Novamarines, Patriarchs of Ulixis, White Consuls, Black Consuls, Libators, Inceptors, Praetors of Orpheus, Genesis Chapter and the Aurora Chapter. It is believed that there were a further eleven or more Primogenitors but the names of these have been lost in the passing of time and no other 41st Millennium Chapters claim the honour.