Ultramar - Ultramar: Ultramar, also called the Realm of Ultramar, referred to in ancient times as the "Five Hundred Worlds" and known formally in the 41st Millennium as Sub-sector Ultramar, is the feudal interstellar empire within the Imperium of Man's Segmentum Ultima that is governed by the Ultramarines Chapter of Space Marines. It is a part of the Ultima Sector in the Segmentum Ultima of the galactic east. It is ruled directly by the Ultramarines' Chapter Master who holds the Imperial noble titles of "Lord Macragge" and "Lord Defender of Greater Ultramar." The name of the realm was derived from an ancient phrase meaning "beyond the sea of night."The commonly used demonym for the citizens of Ultramar is "Ultramarian."One aspect of the Ultramarines Legion that survived the Second Founding was the close relationship between those Astartes and the populations of the surrounding planets. During the Great Crusade the worlds around the XIII Legion's homeworld of Macragge provided young recruits for the Ultramarines. They also supplied raw materials, armaments and spacecraft. At that time, Ultramar was a vast stellar pocket empire comprising over five hundred worlds.Although the need to recruit from these worlds diminished almost to the vanishing point with the reorganisation of the Imperium after the Horus Heresy when Ultramar was reduced to its present, far smaller size on the orders of Primarch Roboute Guilliman, the tradition continued. To this day, the Ultramarines recruit not from a single world, but from the whole sub-sector of their local space. This area around Macragge is called Ultramar, the stellar empire of the Ultramarines.In the wake of the resurrection of Roboute Guilliman during the Ultramar Campaign of the 13th Black Crusade in ca. 999.M41, one of his first acts was to declare the autonomy of many worlds that had once been a part of Ultramar but had been allowed by him to break away after the Horus Heresy to be null and void.With his reclaimed authority as the Lord Macragge and Lord of Ultramar, Guilliman declared the restoration of what had been known during the time of the Great Crusade as the Five Hundred Worlds of Ultramar. When the primarch left Macragge to pursue the Terran Crusade, he left Ultramarines Chapter Master Marneus Calgar behind on Macragge to serve as his regent and over the restoration of the full extent of his stellar empire.After the Great Rift fractured the Imperium in half following the 13th Black Crusade, Ultramar came under assault by the servants of Nurgle, the Plague God, who had decided to add the whole of Ultramar to his Garden in the Realm of Chaos. The worlds of Ultramar were attacked from within and without by Nurgle's forces, including an invasion led by the Daemon Primarch Mortarion and his Death Guard Traitor Legion and the Daemonic Plague Legions led by Ku'gath Plaguefather. These so-called Plague Wars lasted for over a solar decade, until following the official conclusion of the first phase of the Indomitus Crusade at the Battle of Raukos, Roboute Guilliman, now the ruling lord commander of the Imperium and Imperial Regent, finally arrived with reinforcements to aid his beleaguered home.Arriving on Macragge, Guilliman announced that he had made a grave mistake when he had allowed the official borders of Ultramar to shrink so drastically in the days after the Horus Heresy. Instead, he reestablished the ancient ruling Tetrarch Council for Ultramar, and tasked its newly-appointed Tetrarchs, including his Primaris Space Marine Equerry Captain Decimus Felix and the Ultramarines First Captain Severus Agemman, with beginning to expand the territories of Ultramar to include all of the star systems that had once comprised the Five Hundred Worlds.The primarch then launched a counterattack against the Nurglish Chaos Space Marine and Daemonic forces besieging the sub-sector. After cutting them off from their supply lines by retaking the Espandor System, Guilliman forced his brother, the Daemon Primarch Mortarion, to launch the bulk of his forces against Parmenio where the largest armoured clash in the Plague Wars took place.Once the Ultramarines and their allies ultimately gained the upper hand there, Guilliman next struck at the final stronghold of Chaos in Ultramar, fighting his brother Mortarion to a draw on the "Hospital World" of Iax that had earlier been invaded by the Daemonic legions of the Great Unclean One Ku'gath. In the wake of a titanic personal clash on the battlefield between the two primarchs that left both wounded, Mortarion ordered a final withdrawal of the Chaos forces from Iax under the cover of a Virus Bomb assault that cleansed all life from that former Garden World. The Nurglish forces then returned to their base in the Scourge Stars.