The Chaos forces from within the Eye of Terror put aside their rivalries and brought forth the first war on Armageddon! Let’s take a look!
Via our good friends at Lexicanum
The war began within the hated region known as the Eye of Terror. The forces within, being devoted to Chaos, usually fight each other, but occasionally and inexplicably they put aside their rivalries to form an assault on their common enemy, the Imperium. In this case, the unity of the powers of Chaos was triggered by the arrival of the Space Hulk Devourer of Stars around a Daemon World.
The Hulk was large enough to carry a huge chaos force to attack Imperial worlds. The capricious currents of the warp drew the invasion force to the Imperial Hive World of Armageddon in 444.M41.2
Meanwhile, on Armageddon, a series of strange events culminated in armed rebellion breaking out in half a dozen hives. Armageddon consists of three main landmasses. Most human life is located on the main continent, which is split into two parts, Armageddon Prime and Armageddon Secundus, separated by the thick band of jungle known simply as the Equatorial Jungle.
The revolts were quickly put down in Armageddon Secundus, but amongst the more widely scattered hives of Armageddon Prime they proved more difficult to eradicate. As the planetary defense forces seemed capable of dealing with the revolt, no additional units were sent by the Imperium. Armageddon was a very long way from the Eye of Terror, and no one suspected the cause for the revolts was more sinister than simple civil unrest.
Busy containing the rebellion, Imperial forces were caught by surprise when the Devourer of Stars arrived in the Armageddon system.
Primarch Angron
The Devourer of Stars housed an enormous Chaos army led by the Daemon Primarch Angron. Chaos Marines from the World Eaters Legion, cultists, daemonhosts, mutants, beastmen, and hordes of daemonic creatures poured from the space hulk and descended on Armageddon Prime.
The insidious effects of Chaos were quickly felt as nearly half the Planetary Defence Force went over to the invaders. The bloodlust-driven World Eaters descended upon the planets populous with a fury, butchering millions in the first weeks. The few remaining loyal defenders were quickly routed from Armageddon Prime. Falling back through the jungles in the south, the survivors joined up with the units from Armageddon Secundus and prepared to make a last ditch defense along the rivers of the Styx and Chaeron.
