Merir Astelan
Chapter Commander Astelan
Chapter Commander Astelan was a leader in the old Dark Angels Legion, and is considered one of the Fallen Angels.
History
Astelan was one of the original Chapter Commanders from the Dark Angels Legion before the finding of their Primarch, Lion El'Jonson.
After the Horus Heresy and the fall of Caliban, he found himself on a world called Scappe Delve, whose inhabitants were forced to live in underground shelters due to the hazardous nature of the environment. He quickly became tired of living in the cramped confines of the world, so he left the planet on the ship of the Rogue Trader Trialartes, the Saint Carthen.
After finding out that Trialartes was secretly smuggling weapons to unsavory organizations, he accompanied the smuggler to the mercenary port of Port Imperial. Here he met Brothers Methelas and Anovel, two other Fallen Angels. They proceeded to systematically commandeer weapons systems and armour plating from the other ships in the docks, before turning their newly acquired weapons on the ships they were stolen from as well as Port Imperial itself.
Astelan, after discovering that his views for a Greater Imperium differed from the views of the other Fallen, disembarked on the small world of Tharsis. Gripped in the middle of a civil war, Astelan saw his chance to make a difference. He approached Imperial Commander Dax and was immediately put in charge of the Imperial military presence on the planet.
After much bloodshed, Astelan delivered what he had promised the Imperial Commander -- victory. When he realized that Dax meant to institute leaders from the old noble houses again once the war was finished, Astelans 'sacred bands' of elite warriors staged another revolution and killed the Imperial Commander, insisting that Astelan take his place.
Tharsis had been primarily a farming world until Astelan's arrival, after which it was dominated by crime-rife cities and sprawling factories for making the weapons he used to win the war. During the final stages of the revolt against the Imperial Commander, one lone space pod had gotten out of the system and placed a distress call. The call was picked up by a Dark Angels ship passing by the sector, who retrieved the survivor and learned the story.
The Dark Angels sent Interrogator-Chaplain Boreas to investigate, who ended up fighting Tharsis' soldier population until Astelan realized who had come to the planet he now ruled. Astelan gave the order to stand down and allowed the Interrogator-Chaplain and his Deathwing retinue into his command bunker, where he was placed under arrest and taken off-world for transport to the Tower of Angels for interrogation.
In the span of fifteen days, Boreas and his Librarian assistant Samiel pried at Astelan's mind with pain, torment, psychic abilities, and questions designed to undermine Astelan's view of the events that occurred, trying to get him to admit his sins and repent. Astelan struggled and survived, explaining much about the past of the Chapter and the old Legion before the Heresy. He explained that it was his order that set Caliban's guns ablaze against Lion El'Jonson's fleet when it returned, and he revealed that it was his voice that was lent to Luther when the Space Marines on Caliban were uncertain that they were being led in the right direction while watching over the planet.
After his interrogation, Astelan was taken from his interrogation chamber by Sapphon, the Grand Master of Chaplains, and placed in a cell in the deepest catacombs of the Rock, where he lives hearing Luther cry out for salvation.
Sources: Angels of Darkness (novel), by Gav Thorpe