The Emperor's Swords is a Loyalist Space Marine Chapter of unknown origin and Founding and the first of two separate Chapters to bear the name. The Chapter was decimated by the forces of the Alpha Legion after 300 standard years of infiltration and subversion on its homeworld of Ghorstangrad. A second Chapter to bear the name, this one settled on the Chapter homeworld of Bellicas, would also be destroyed, this time by the awakening of Necrons beneath the world in 970.M41.
The first iteration of the Emperor's Swords was decimated by the machinations of the Alpha Legion Chaos Space Marines. For over a dozen generations the Alpha Legion manipulated the slums, gangs, and sects of the Emperor's Swords' homeworld of Ghorstangrad, a heavily populated Imperial Hive World. The Alpha Legion's operatives placed subconscious triggers in the rituals used by the gangs and sects who inhabited the Underhives of the planet's various hive cities. It was from these gangs and sects that the Emperor's Swords recruited new Space Marines for their Chapter.
- Decimation of the Emperor's Swords (Unknown Date.M41) - When the Alpha Legion finally launched its assault on Ghorstangrad, it was able to use the subconscious triggers it had placed within the Emperor's Swords recruits to disorient and confuse a good number of the Loyalist Astartes. These members of the Emperor's Swords even turned on their fellow Space Marines. In the ensuing chaos, the Emperor's Swords ceased to be a functional Chapter. Some of the survivors turned Renegade and joined the Alpha Legion. Those that died at the Traitors' hands had their gene-seed harvested for use by the Alpha Legion in creating new Chaos Space Marines. As for Ghorstangrad, it fell to the control of Chaos and became a stronghold for the Chaos Space Marines.
The Emperor's Swords primarily wore metallic silver Power Armour. The Aquila or Imperialis on the chest guard, as well as the shoulder plates, were red. The black squad specialty symbol -- Tactical, Assault, Devastator or Veteran -- was located on the right shoulder plate. A white Roman numeral was centred on the squad specialty symbol, indicating squad number. The colour of the helmet stripe was used to denote company number in accordance with the Codex Astartes -- i.e. White (1st Company), Yellow (2nd Company), Red (3rd Company), Green (4th Company), etc.
The Emperor's Swords' Chapter badge was a large white skull pierced through by two intersecting ebon swords on a field of red.
There is some ambiguity in existing canon in regards to the existence of the Emperor's Swords Chapter. Apparently there were two Space Marine Chapters named the Emperor's Swords, and both were destroyed in their entirety. The first was decimated by the insidious actions of the Alpha Legion on their homeworld of Ghorstangrad, after its Initiates were subverted by the Alpha Legion for 300 standard years. The world then fell to Chaos and became a stronghold for the Chaos Space Marines. The second Chapter to bear the name was destroyed when the automatons of a Necron Tomb World stirred to life beneath their fortress-monastery on their Chapter world of Bellicas in 970.M41.
- Adeptus Astartes: Successor Chapters (Limited Release Booklet), pg. 40
- Codex: Chaos Space Marines (4th Edition), pg. 21
- Codex: Necrons (5th Edition), pg. 27
- Codex: Space Marines (5th Edition), pp. 30, 49
- Warhammer 40,000: Rulebook (5th Edition), pg. 144
- White Dwarf 390 (US), "The Battle for Cardrim," pg. 30