The Shrine of Unity was a monument to the completion of the Unification Wars in the Sol System erected during the years of the Great Crusade. It was situated upon a grandly-sized comet that observed an elliptical orbit around Sol -- routinely swinging back into Terra's solar system. The comet had been seen in the heavens when the Emperor had secured the Unity of Terra, and it was for His victory that the shrine was created on the solar object.
In the year before 132.006.M31, the Word Bearers' Captain, Sor Talgron, visited the Shrine. This was noted by the Primarch of the Imperial Fists, Rogal Dorn, who had been recently tasked with defending Terra in the wake of the news concerning his brother Horus Lupercal's betrayal at Istvaan III. Dorn questioned Talgron, and was told by the dour Word Bearers warrior that his own Primarch, Lorgar Aurelian, had asked the Captain to remove "certain edifications" from the comet, before its return to the Sol System several years hence. These supposed edifications dated from before the Word Bearers' censure at Monarchia forty standard years earlier -- meaning that they were a proclamation of the divinity of the Emperor as a god, which contravened the secular Imperial Truth.
The removal of such objects made sense to Dorn, for he believed the truth of Talgron's words. In reality, Talgron was not in fact removing pre-Monarchia religious objects, but committing acts of sabotage against the Imperium in the Sol System ordered by Lorgar. Talgron's task was incomplete at the time of Dorn's return and his call to their meeting, as he later told his Chaplain-turned-Dark Apostle, Jarulek. Talgron left a contingent led by a Word Bearer named Ibarix to finish the job, though Jarulek noted that their fate was a death sentence. Talgron proclaimed that Ibarix and his fellows would do the XVII Legion proud when their time came, a reference to the future assault by the Traitor Legions on the Sol System and the Battle of Terra.
- The Purge (Novella) by Anthony Reynolds