The mythical origins of Eberron by the Progenitor Dragons.
From the birth of the world to the modern day, much of Eberron's history is steeped in mystery, myth, and story, but there are many scholars and mages that have studied ancient texts and works to fit together a timeline of events that leads to the modern day.
As the world solidified, Demons came to the surface to rule over the Dragons' creations. Eventually, the Dragons and Couatls banded together to seal them away, ending the Age of Demons.
An age when Giants ruled over the Eberron, clashing with a race of interplanar beings known as the Quori. After utilizing world-ending magics, the dragons destroyed the Giants, ending their reign over the world.
Monsters take the place of the once proud Giants, reshaping the world once again. Eventually, internal strife fells their nations, leaving room for the age of humanoids to begin.
Humanoid races thrive as the dominant races of Eberron, and Dragonmarks emerge among them. Kingdoms rise and fall, most prominently the Kingdom of Galifar in Khorvaire, which crumbled into a hundred year civil war known as the "Last War". Peace has been found in Khorvaire, but tension still run high, and the future is not yet set in stone.