Hey guys, I was hoping to lean on some lore-ninjas a little more up on the Heresy than I am. In going through the black library series I am currently caught up through Betrayer, and as the Primarchs are a large focus of the HH series I cannot help but try to put some order to their descent into madness. I am not sure if the following counts as SPOILERS but consider yourself warned.
Based on what the novels has listed, this is a rough timeline for the fall of the traitor Primarchs. (Time listed in relation to the Drop Site Massacre of Istvaan v ~ 006.M31)
DSM -40: Lorgar reaches EoT and Cadia. Catalyzed 3 years earlier by Erebus and Kor Phaeron
DSM -6: Fulgrim acquires the blade of Laer which begins his downward spiral.
DSM -5: Alpharius/Omegon have their revelation with The Cabal. Unclear if they are actually under the sway of Chaos (at least at this point).
DSM -2: Horus falls to the Anathame at Davin. Events are catalyzed by Erebus.
DSM -2: Perturabo commits genocide against the rebellion on Olympus and realizes he is beyond forgiveness. Events catalyzed by Horus
DSM -2: Mortarion , Angron , and Fulgrim are called to meet with Horus and brought to his cause. It is possible that Mortarion was receptive due to the influence of Erebus by way of Typhon
DSM -2: Magnus the Red suffers the loss of Prospero and accepts the 'salvation' offered by Tzeentch. He appears to have achieved Daemonhood.
DSM +0: The Drop Site Massacre of Istvaan V. Open Rebellion by Sons of Horus, Iron Warriors, Alpha Legion, Night Lords, Word Bearers, World Eaters, Death Guard, and Emperors Children. Magnus responds to Horus' invitation.
DSM +1: Perturabo and Fulgrim seek out the Angel Exterminatus. Fulgrim achieves Daemonhood.
DSM +2: Lorgar and Angron attack Ultramar. Angron achieves Daemonhood.
So with all the laid out the big question mark I have is Konrad Curze. The two stories featured in Shadows of Treachery, show his confrontation with Dorn as occurring before before the heresy has broken out, and it seems as if he was being recalled to Terra around the events of Istavaan. So the two queries I have are: have we seen exactly when Curze decides to throw off his loyalty to the Emperor? He's certainly unstable, but he seemed to try to be consilatory in part during The Dark King. Question #2. IF Curze was on the lamb, and marked for reprimand, when all hell breaks loose with Horus, should not the loyalists have suspected him FIRST when they heard legions were rallying against the emperor? Magnus was already on the black list, and they knew Horus had at least 4 legions, so I cannot think that the tactical commanders be they the Emperor, or just Dorn and his Ilk would have said "Oh! Curze, you're coming to help us pacify Horus? That's just tops!"...and not have expected a knife in the back.
Perhaps one of the later books covers this, but I haven't seen his stance explained so far.