William James, Talks to Teachers on Psychology and to Students on Some of Life's Ideals (1911).
Brutal, ruthless and unwavering but also honourable, and once loyal beyond question, the history of the Black Legion is the history of the ambition of the Imperium itself, and the flaws that broke its founder's dreams of unification and glory for all Mankind asunder.
After Horus' treachery and final defeat at the Battle of Terra during the Horus Heresy, however, the Legion was renamed the "Black Legion" by its new Warmaster, Abaddon the Despoiler.
The new name was chosen after the Astartes of the Sons of Horus painted their Power Armour black in grief at the death of their Primarch Horus and shame at their failure to overthrow the False Emperor and seize control of the galaxy in the name of the Ruinous Powers.
Born as the XVI Space Marine Legion on Terra, the Black Legion would first rise to greatness under the name of the Luna Wolves.
Before the dark days of the Horus Heresy they fought at the Emperor's side on Terra and through the early years of the Great Crusade.
Along the way, he encounters a cast of eccentric characters and tough cases.