I am reading Asunder at the moment, and came across a description of the effects of lyrium when entering the Fade. for those who haven’t read, it’s descibed as having this song that overpower the senses. Now, I knew lyirum had a song, but I’d not realized how strongly it comes across as it’s quite difficult to convey in game. That made me think of a few things related to the Titans and the dwarves. I’m not the best at explaining stuff, but here it is.
The more I think about it, the more I believe dwarves are old, really old. Older than the other races, even the elves. They lived in harmony with their titans (uncertain if the Titans actually created them, like dwarves created golems, or if they simply evolved in symbiosis to the Titans they lived in) and the Titan’s Song, as transmitted through lyrium is what allowed them to share in the Titan’s global consciousness. You can say the Song is the Titan’s voice, they way to communicate, and dwarves can understand it in a way other species can’t. That would explain why they are mostly immune to lyrium (at least to a point). After all, they evolved with it and its Song.
Then, the elves happened *ominous music*. Some of them (the evanuris I would bet) somehow found out that one of the properties of lyrium, apart from being Titan blood, is to facilitate magic (by which process, I’m not sure, other than to think the Titans themselves are related to the Fade in some way). In their arrogance, they thought they could kill Titans and take that lyrium for themselves, along with “something else” (the Titans’ knowledge perhaps? By that point in time, I’m guessing Elvhenan wasn’t yet at the peak of its power). They considered the dwarves soulless, because they had no connection to the Fade perhaps, which they might have equated to having no soul, and so waging war on the Titans seemed justified.
Mythal, finally, managed to “slay” one of the Titans and they started mining it and most probably stole whatever they could from it. with their new knowledge and with the boost offered by the mined lyrium, Elvhenan prospered, reaching a golden age. The victorious Evanuris became gods in the eyes of their People. The dwarves from that Titans, cut off from it, became the first dwarves with free will.
All would have been well, if not for the fact a Titan never truly dies. Instead, in time, Mythal found something disturbing in her mine. The lyrium was becoming slowly corrupted by something, a warping of the dead Titan’s Song. And that song was even more powerful than the normal one, bringing everyone into its web that would listen. It corrupted dwarves, elves, anything alive. And thus we have the very first darkspawn. Mythal was intelligent enough to realize the approaching catastrophe as even the Evanuris didn’t have the magical strenght to cure what would become known as the Blight. Killing a Titan was the worse thing anyone could do.
Now, I’ve said before that I think some of the Evanuris couldn’t leave it well alone and the Blight have have been the reason for Mythal’s murder and the raising fo the Veil, so I won’t repeat myself 
Finally, I think the other Titans might have been forced to sleep when the Veil was raised, if truly their relationship to the Fade was that close. Same as some of the elves in Uthenera, they now can’t wake up. the song they sing still exist but it’s probably directionless as of now (like someone muttering it their sleep
). Not having the Titan directing them anymore, the rest of the dwarves gained free will.
I’m also wondering if we’re wrong about Mythal’s reckonning. What if it’s not the the Evanuris she is after, but the Titans themselves? If truly they’re at the origin of it all. The Blight might be considered a betrayal of the world.