Can I just say how happy I am that so many of you want to participate in the discussion? I've learnt a lot of interesting facts and theories that I hadn't thought of or payed attention to before. 
The only thing that lends credence to some idea of Andraste being an old god reborn is that the people of Haven start thinking that a dragon could be Andraste reborn, which is odd unless they knew she occasionally manifested as a dragon. However, I still think that she was linked in some way with a powerful spirit, may be even a Justice spirit since her chant is basically a blue print for a more just and fair society where people who have particularly gifts, like mages, use them for the benefit of others rather than to amass power. It always seemed rather sad and ironic that Andraste condemned the abuse of power and yet that is exactly what the nobles of Orlais and elsewhere do with the peasantry and particularly the elves, and the Templars and the Chantry do with respect to mages. It is simply Tevinter in reverse.
The indwelling of a spirit could also account for Maferath's actions. Remember how possessive Justice becomes over Anders and if you are a rival, how he basically tells you to get lost if you are trying to persuade Anders to stop what he is planning. Now there is a theory given in the codex that it wasn't so much jealousy but that Maferath realised that he couldn't keep going indefinitely with his army and certainly not long enough to totally defeat the Magisters, so he wanted to stop and negotiate a truce while he was still in a strong enough bargaining position to do so. If he suggested this to Andraste and her spirit objected, this could have led Maferath to realise the only way he was going to be able to stop it would be with the aid of strong magic, in other words the Magisters. It would also account for why they insisted on burning her. The Magisters knew that spirits can inhabit and continue to exist in a dead body, and Flemeth has shown that you only need a small bit to reassemble yourself, so the only way to ensure that the spirit did not use her body to continue its work was to utterly destroy it.
If it's something I gained from The Masked Empire, it's that Orlais is really not that much better than Tevinter when it comes to abusing power and oppressing others, especially the Elves. Both empires have repeatedly tried to annex Nevarra and the Free Marches, as well as Ferelden during the different ages of Thedas. As you point out, unlike Andraste, most of those with great powers doesn't seem to want to use them for anything other than gaining influence and power for themselves. Maybe that's what really made her unique and allowed her to lead so many and together change the world.
It's interesting to consider that IF Andraste was possessed by a spirit, that it may have talked to Maferath. The Ash Wraiths in the Gauntlet are probably not truthful with their recitation of Maferath's intent and betrayal. It makes sense, if the theory of him trying to be realistic is true, that as a skilled warlord he'd realize that they couldn't keep it up forever. It doesn't make it any less sad though.
One more point, it would also account for why the Maker was said to be willing to return to help mankind if they world followed the Chant and then apparently abandoned them after the death of Andraste. The spirit she was communing with simply retreated back into the Fade.
An excellent point to your theory! Thanks for sharing. I like my OGB-Andraste theory personally, but I wouldn't be surprised nor disappointed if your theory is closer to the actual truth, if we'll ever find that out in the game.
Andraste is almost definitely a slightly more ruthless Bethany-type mage to me, and her being an OGB would be interesting, but is is even possible? Part of what makes the Joining the Joining is Archdemon blood, which they probably wouldn't have until after the first Blight, yes? And the ritual is said to only work with Grey Wardens, who are different from your standard early-stages-of-the-taint people? Unless of course it could work with a pre-ghoul.
ETA: it'd be nice to know if the blood from the Archdemon's corpse if it's not permanently killed has the same properties as permadead blood. It does make more sense, now that I think about it, if the blood is the same, because then they have a renewable resource for making new Wardens during those centuries-long Blights. So I suppose it's possible.
Good catch! Since the First Blight is characterized not only by it's length, but also mainly by the fact that the Archdemon was falsely assumed to have been defeated once, this was probably the case. Dragons as a source of power in Thedas is a repeating theme as I've pointed out. So the Grey Wardens needed to kill the Archdemon at least once in order to fully defeat it, whether they knew it or not. They probably stood over the defeated carcass and tried to figure out if they could harness some of it's power, had a few Wardens try it out and then eventually realized that the Archdemon was still alive somewhere from the dreams and whispering.
Since the Qunari knew about Calahad Theirin using dragon's blood for reaving, perhaps Sten and his men were sent out by the Arishok to find out more about how the Wardens could actually kill the Archdemon, which is shaped like a dragon. I'm planning on having a discussion about Qunari later, but their horned, dragonlike appearance certainly is curious.
I can fully accept Andraste being what the Chant says she is, but what a religious text says about a prophet and religious institution says about that same prophet can often be quite different. And she is Thedas-Jesus.
Well said! I'm sure that Bioware have taken great care to set their world up in a way that the absolute truth of things is rarely known by any one person, nation, people or institution. Otherwise, what would we find out as the DA-series went on?
During the Gauntlet the spirit of Cathaire said that the Tevinter fell due to famine. He speaks of the sun burning the crops. But I'm more inclined to believe that a dragon burned them down. Or a woman that can shape shift into a dragon that happens to be Old God of Silence.
Interesting theory! I only wonder, if that was the case, how the Chantry has been able to surpress people from spreading this knowledge, like The Dragon Cult of Andraste, eyewitnesses and historians. Would this fact have been known by those who followed Andraste in her army, or would she have transformed in secret?
(...) the "singing" is so prevalent in the DA universe that it has to be a manifestation of something universal.
- Lyrium sings
- Red Lyrium sings
- The Taint sings
- Andraste sang and the Maker...came? Became?
When you consider the last point (as you noted) the whole Maker will return with the proper chant thing is pretty intriguing to think about. Are there other examples of resonance? Frequency? Singing? Chanting?
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On another note, I've always been aware that Corypheous jumped upon his death, but never realized that's likely exactly what Archdemons do. Except that his soul wasn't obliterated. Why? I thought the Grey Warden deathblow worked because two souls couldn't inhabit a single body, but Cory presumably didn't have a problem with it.
So let me get this straight...it's OK for two human souls to coexist (Cory and GW host), and it's OK for a soul and a demon/spirit to coexist (Anders, Wynne), but a Grey Warden and an Archdemon annihilate each other. How is an Archdemon different? Obviously, I didn't think it was a human soul, but I did think it would be a spirit of some kind. But apparently, it is something...other.
This would suggest another type of entity, of which I'd propose the Maker, the Archdemons, Flemeth, and Fen'Harel are of. Perhaps these entities can only be created/summoned/manifested/instantiated by creating the proper resonance. Perhaps the elves manifested the old gods; the Tevinters brought the Archdemons into existence; and Andraste made the Maker.
Perhaps it takes a powerful dreamer? Perhaps Andraste was an uber-dreamer along the lines of the early elves and the most powerful Tevinters.
Interesting to read several posts pointing out the importance of songs in Thedas. I agree that the focus on song in what appears to be separate matters might be a hint of a possible connection. We'll get more into that when we discuss Red Lyrium I guess.
One of the reasons that I think the Grey Wardens are hiding something about the destruction of the Archdemon and the Grey Wardens that strike the killing blows is what you point out: What makes the Archdemon's soul behave differently, when others can co-exist with spirits and souls? We know that demons take over their subjects, but the wizards' souls still exist in the body, albeit suppressed and controlled by the demon. Wynne and Anders co-existed, the former quite peacefully, Anders more disharmoniously with both him and Justice affecting the other. Corypheus appears to have hitched a ride with a Warden without the possessed subject even noticing the fact, and he certainly didn't seem to need permission the way that Justice (and supposedly Wynne's spirit) needed Anders' permission. And if I'm not completely misremembering, demons need permission to possess living, intelligent beings (as opposed to Sylvans, etc). And yet, Corypheus just...slips into Larius or Janeka, though they both may of course have unwittingly given their permission, seeing as they'd been under his influence for quite some time when we come across either of them.
Perhaps the Archdemon can only possess mindless, tainted creature, like the other darkspawn, and it's soul is destroyed (or possibly purified) because the Grey Warden is an intelligent being? Would that make sense?