It was intended for the Horus Heresy Compendium to contain a brief explanation about the characters and notable battles during that period but due to the amount of content still unwritten I have decided to make it in two parts. 1 for characters, the other for battles and places.
Effort has been made to create a brief synopsis of every character, while inferences of the fates of certain characters given in entries of other characters to create an overlapping chain of entries which when read together, tell the rough story of the Horus Heresy.
It is with great regret that several organizations (White Scars, Salamanders, etc) are woefully under represented due to the lack of written background information.
Reader beware: mild spoilers abound.
The Terran Administratum and Council of Terra
The Emperor of Man
Is created and formed by / with the reincarnated souls of the shamans of Terra to combat the threat of the Chaos Gods. Guides humanity from the shadows before appearing in the open during the Age of Strife. Enters alliance with Mars and attempts to wipe out religion in a campaign known as the Great Crusade.
Malcador the Sigilite
The strongest psyker after the Emperor and Magnus the Red, the founder of the administratum and the Council of Terra. The Emperor's regent and first Grandmaster of the Assassin Temples.
Lord of Hy-Brasil,double agent for Rogal Dorn's spy network, with links to the Warmaster himself. He was killed by an assassin posing as a Lucifer Black.
Other members: Ormond Braxton, Emissary
Vadok Singh, Warmaston of the Imperial Palace
Dark Angels Space Marine Legion
Primarch of the Dark Angels. Found on Caliban by the Emperor shortly after ridding the world of Chaos beasts. Known to be sullen and brooding but a tactical genius and a master of the blade as well as a beautiful singing voice.
Dark Angel Librarian. The only other Calibanite to have slain a Calibanite Lion. (The other being.... Lion.) Discovers latent psychic powers shortly after. Enlisted in the Legion as a Space Marine when the Emperor arrived.
Right hand of Lion El'jonson and the one who found him and named him. After briefly serving in the Great Crusade, Luther was sent back to Caliban along with Zahariel among others. Driven mad with envy Luther would later turn on his Primarch.
Chapter Master and known member of the Order of the Raven's Wing on Caliban. Astelan is known to have clashed with fellow commander Captain Belath of the same Legion. Is present when Luther decides to fire upon El'jonson's fleet.
Chief Librarian of Terran descent, is the first to recognize Zahariel's latent psychic abilities and thereafter vouched for his induction into the Librarius.
Cousin to Zahariel, they were involved in a plot to assassinate the Emperor following His arrival on Caliban. Zahariel however, managed to foil the plot and was vouched for by Israfael. Nemiel later remained by the side of the Primarch following his cousin and Luther's return to Caliban.
Other Legionnaires: Hadariel, Chapter Master of the 22nd.
Emperor's Children Space Marine Legion
Primarch of the Emperor's Children Legion. His speech upon meeting his Legion moved the Emperor to allow the III Legion to be renamed to the Emperor's Children and to allow them to be the only Legion of that time to wear the Aquilla.
Holding the title of Lord Commander, Eidolon led a contingent of Emperor's Children to a world called Murder, where his foolhardy attempts at snatching glory ended with him needing to be rescued by the Luna Wolves. His reputation with the Warmaster has since lowered considerably.
The other Lord Commander of the Legion, Vespasian was loved by all. Attempted to stop the Legion's degeneration into Slaanesh's ideals and was later killed by Fulgrim for his trouble.
Apothecary of the Emperor's Children, he is the first known individual to have directly tampered with Space Marine gene-seed, using elements from xenos biology to enhance the Legion's Marines.
Dreadnought and Keeper of Rites for the Legion. Deemed to be incorruptible, he was sent to the Choral City to die by the hands of his own Legion.
First Captain of the III Legion. Followed his Primarch to damnation, leading the Phoenix Guard, the Legion's Terminator elite aboard Ferrus Manus' ship, and slaughtered their Iron Hands counterpart, the Morlocks.
Captain of the 2nd Company and due to his transport crashing en route to the battlefield, he was not affected by Slaanesh's taint and was later deemed to be too loyal to the Emperor and was sent to the Choral City to die.
Third Captain fiercely loyal to Fulgrim and the first Noise Marine.
Captain of Tenth Company, Saul Tarvitz enjoyed a good relationship with Garviel Loken and Tarik Torgaddon of the Luna Wolves. He is responsible for bringing news of Horus' treachery to the loyalists Space Marines and prompting the Death Guard's Nathaniel Garro's escape aboard the Eisenstein.
Captain of the Thirteenth Company and said to be invincible with a blade. The best of friends with Tarvitz until envy got the better of him in the battle for the Choral Palace. Betraying his fellow loyalists and slaying Solomon Demeter in the process, Lucius returned to his Legion.
Chaplain of the 18th Company, he fought in the