An email I sent to an acquaintance who is writing a very wish-fullfilling fanfiction.
I've tried to stray from speculations because, well that won't give me answers and I really do need them. lol. It would be a long read of information, but I'd be happy to give you what I believe might be going on in truth, minus wish fulfillment of coarse. In short, The blight is Andruil's fault (indirectly) and known Elvhish is what I've based it off. Andruil got bored of hunting men and choose to hunt the Forgotten Ones (creatures of disease, fear and malevolence) in the Void. Each time she traveled there she came back mad. She forged known armor and weapons (A spear with unbearable heat *I think it's that stupid red idol to be honest) from The Void to help her. *I believe this from the Elvhen word Banalhan. It means 'the place of nothing", a name for the Blight or it's place origin as mentioned on Dragon Age Wikia whould you wish to look it up. When Andruil came back, sicken her lands and people, she brought it back with her, but was unaffected because the Elvhen's tie to the Fade (lost once the Veil was put up) kept them immortal and Mythal subdued Andruil and took the memory of how to get into the Void *Which I believe is the whispers heard from within the Black City* The song behind doors whispers want opened" As Cole quotes it. I further this idea with the writings engraved in red lyrium.
We are here We have waited We have slept We are sundered We are crippled We are polluted We endure We wait We have found the dreams again
Now I believe that the Old Gods are the same as the Forgotten Ones (hinted at by David Gaider) they desire to be freed from their confinement.
Let me pull you back just a bit. If An Elvhen Mage with immortality brought the Blight from the Void, how is it spreading? I'm sorry to say I think this is on Mythal's head. After Andruil came back ill, it's known her lands became sickened and began to decay (like what happens when large amounts of Darkspawn come together) this sickness reached down until it took hold of a titan and to stop the spread Mythal killed it, but the titan's blood seeped back into the ground and slowing began reaching out; Titan and Dragons alike. Saddlythe Magisters moved against The Golden City first where they caught the blight. *I believe that some of the Magisters were in fact women and became the first Broodmothers for the horde.* Horrified by the sickness creeping up on them they condemned the city and they spoke before the blight took them that it was a place of decay and disease. Hense why something in Fade which changes based on each dreamers perspective looks the same. Because everyone thinks its black. Everything snow balled from there. Red lyrium slowly grew at first because cool temperatures and only goes haywire once in contact with warm, living, breathing, things. Which is why the Red Templars grew it in Emprise du Lion as it was stabilized by the cold.
Now the blight has caused infertility issues among the Dwarf race and having relative peace only when the Darkspawn horde to the surface being their only reprieve doesn't help. The Titans were hunted by the Evanuris "to free their mindless subjects and forced growth from their corpses" "Lyruim was then mined from their bodies and an eon later the mines were sealed away". I think they found use in the lyrium, but the taint had spread and thus why when you find the Red Idol in DAII you find it in a Thaig that predates the Blight.The Elvhen placed it there and sealed it up, the weapon of Andruil.
I've yet to hear back from them, but I hope they enjoyed my perspective and that it helped them or inspired them in the least. XD