Part Three - The Successors of Ultramar
When the galaxy burned brighter than ever and the Imperium faced its final challenges, the Realm of Ultramar stood.
The home of the Ultramarines and many of their Successor Chapters stood, even as the rest of the Imperium faltered and flickered. Their defenses had weathered the fearsome plague that was the Death Guard during the Plague Wars, produced some of the finest warriors in the Imperium, and was perhaps by the end, the last standing proper Imperial stronghold as the entire Imperium crumbled and splintered as the Emperor's sword clashed against Khornate brimstone, layers of putrid flesh, unknowable magics, and weapons forged from the souls of a doomed race.
After the collapse of the Imperium and the Emperor's supposed demise, the Realm of Ultramar no longer maintained its last stand unity. Not granted the final glorious death promised to them by unending waves of daemons pouring like a terrifying flood from the shrieking Great Rift, Ultramar split into four Successor Nations.
The first of which is the Realm of Sicarian, or Ultramar Empire, with Macragge itself as its capital, ruled by Cato Sicarius and the House of Sicarian, chosen few Astartes and mortals alike called upon to replicate a sort of 'royal family'. Though 'Grand Captain' Cato is the supreme ruler, his advisors and lower-ranking governors all reside within the House of Sicarian. In order to obtain any sort of power or even rights within the Realm of Sicarian, one must cast off any previous loyalties and must accept the Grand Captain as their surpreme overlord. Without an Emperor to worship, he encouraged his people to believe him one to worship, and so after thousands of years of survival against the three other Successors of Ultramar and their neighbors, the Tau Empire, their rebel AI state, the Phoenix Imperialis, and the final Necron Tomb World, Cato Sicarius has earned a respectable degree of admiration by dueling many other champions. Shadowspear, a Man of Iron, Necron Overlords and even Lucius himself have locked blades with the Grand Captain at least once.
Though he has failed to kill Lucius, their rivalry has become so great that in the Sicarian Ecclesiarchy and their religious texts, Lucius is the devil to Sicarius's god.
Sicarius's empire has the most military assets in the shattered remains of Ultramar; veterans of the Wars Before and new Astartes numbering in Legion strength and billions of Guardsmen are backed up by one of the largest navies in the galaxy, near a dozen thousand ships in total.
Second of which is the Guillimanites, the true successors to the Realm of Ultramar. They are the smallest of them all, but their moral integrity and heroism echoes that of Guilliman himself by the end, who had seen the lies of both Chaos and the Imperium, and prepared to build a nation pure of heart before disappearing during the final battle of the Age of the Imperium. Led by a Space Marine simply named Titus, a hero thought lost during the chaos of the forty-second millennium, the Guillimanites, while only four systems in number, show unbreakable will and terrifyingly competent forces. Each Space Marine, each Guardsmen loyal to Titus can kill five, eight of their counterparts across the galaxy.
This is due to the way the Guillimanites are run. Titus's forces are taught the Codex Astartes, and the later Codex Imperialis, but are educated in his school of thought. Where the forces of the Realm of Sicarian may stick to the doctrines laid out whole-sale, the soldiers of the Guillimanites often abandon its teachings in the name of adaptability and quick thinking. Knowing the tactics of the enemy while being able to change your own has earned them many victories, and Sicarius's contempt for Titus and his people grows by the day. While he may not have the waves of soldiers of Sicarius's empire, he has soldiers with five times the quality. With seven hundred Space Marines, two hundred million Guardsmen, and a modest fleet, the Guillimanites are surprisingly effective and even gaining ground against the evils of Cato Sicarius.
The third is the Realm of Angels, the Dark Angels who sought refuge within the hallowed realm of Guilliman after the tragedy of Luther's betrayal was spread by Luther himself. Paranoid, drab, and with a hunt for the traitors that will likely never end, these sons of the Lion show little interest in the politics and warfare between the states of Ultramar, though they have raided both the Guillimanites and Realm of Sicarian for supplies and vice versa.
The fourth is a new player, one that sprung up from lost colonies and unchecked regions within the former Realm of Ultramar and beyond. The Nova Legion, presumed descendants of the once-noble Novamarines Chapter, have returned with glory in their eyes and vengeance in their hearts. Rivaling the Realm of Sicarian in size and even surpassing it in forces, even the glory-mad Cato Sicarius, secret warriors of the Realm of Angels, and firm but heroic Titus have called ceasefires to repel the Nova Legion's assaults. Led by an Astartes who dared to take up the name of Roboute Guilliman, they have declared those who take up the space of Ultramar to be heretics and foes to be slain in the name of 'reclaiming the old glories of Ultramar'. Wielding the Fists of Ultramar, this Primarch imposter has declared war on all other three nations. "The Realm of Sicarian is led by a man with drive but without the caliber required to complete his dreams of divinity and stifles Ultramar's return to greatness. Titus's men are 'merciful' and 'compassionate', weaknesses that should not be tolerated by any man claiming the name of Guilliman as their nation's title. And the Realm of Angels? They aren't even Ultramarines! The infestation of secret traitors and blasphemous knights will be purged with more prejudice than the perversions of the Ultramarian dream."
Lurking ever in the shadows of these great wars, yet another enemy brews, from the ashes of a long-dreaded species...