Celestium

Also known as the Light or the Beginning, Celestium is the lower division of the Monumidium where the Eah dwell. It existed before the formation of Ebdypha. Celestium and Astrium were mixed together between the time when the Eah ruled over the Aidrus, and the time when Heocalan banished the six strongest Eah from the Monumidium.
Celestium itself is a realm of divine light, symbolic of existence in its totality, of divine knowledge and power, and of potential. It was ruled over by Fallasar, the highest of the Eah, but after he was banished, the Eah did not elect a new leader, and instead found a way to exist in peace alongside the Aidrus. As with the Aidrus, the Eah who remain in Celestium do not interact with the mortal realm of Domos, though there are times where the Firmament which separates Domos from the Monumidium is broken, such as the Enlightenment that ended the Relict Age and brought about the Young World. The breaching light of Celestium is powerful enough to kill Domos-bound Eah and give full sentience to humans and other creatures.