Long ago, when the people of the volcanic world of Chaarissa realized that there were worlds and peoples scattered across the night sky, they wept. How many millions of souls languished in the cold and dark, untouched by the love of the Flame Lords? Immediately, they knew what they must do: it became their holy mission to bring the light of the Glorious Dawn to the multiverse.
The Heralds of the Glorious Dawn are an entire civilization mobilized to a religious crusade. When their mighty cathedral-ships descend upon a new world, the warrior priests march forth in ranks of shining golden armor and offer the populace a simple choice: convert to the worship of the Flame Lords, or burn on the pyres of purgation. Conquered worlds are quickly remodeled in the Glorious Dawn's monastic style, with the population laboring under strict religious oversight to produce war material and conscripts for the Glorious Dawn's next conquest.
The creed of the Glorious Dawn revolves around the veneration of elemental flame spirits known as the Flame Lords, and spreading the worship of them to as many people as possible. They acknowledge the existence of other deities, but seek to destroy them.
The high priests and elite warriors of the Glorious Dawn are known to be possessed by Flame Lords in a symbiotic relationship that bestows tremendous power upon them.