The Story of the Mithrilar, Arnor, Dread Lords, Humans, Altarians, and Drath
The Galactic Civilizations Universe - The Journey from Then to Now
Being the last of the good Mithrilar, I Mascrinthus, know the truth. 
If you read the dev journals you can piece together the truth.
At the end of the GalCivII campaign, DL Bradley travels to the Dread Lord's pocket universe. Over time he learns all their secrets and more. He becomes as powerful as the Mithrilar and escapes from the pocket universe into the distant past. However, over the eons his sense of the passage of time causes him to go mad! DL Bradley has become Draginol!!! He creates the Arnor and the Dread Lords. At the end of the Arnor vs. Dread Lords war, the Dread Lords are sent to the pocket universe and Draginol is sent to the Drath's home world. There he creates the Altarians in his image; they displace the Drath and rename the planet Altaria.
At the end of the GalCiv II campaign, the Thalans try to stop DL Bradley from entering the pocket universe. In various posts it is suggested they are time travelers and they seem to know of the loop in time.
Sources:
Dev. Journal Post 2006/02/13 The Galactic Civilizations Universe - The journey from then to now
Dev. Journal Post 2006/07/23 The Dread Lords, the Arnor, the humans and the Altarians - The mythology of Galactic Civilizations
ImpulseDriven Post 2007/12/30 Of the Altarians
Dev. Journal Post 2006/07/28 The Reluctant: Chapters 1-6 (Act I) - Legacy of the Orb
JoeUser.com Post 2006/08/12 The Reluctant: Chapter 7 - Legacy
JoeUser.com Post 2006/08/15 The Reluctant: Chapter 8 - Destinations
Elemental Forum Post 2008/12/30 Excerpt from "Guardians of the Telenanth" - Appendix D: The Tragedy of Draginol & The Arnor
Elemental Forum Post 2009/01/05 Excerpt from "Guardians of the Telenanth" - Appendix B: Draginol & The Morning Star
Paul D.
