Board Thread:Lore Discussion/@comment-89.243.7.241-20130820154309/@comment-64.189.216.70-20151002041043

Ysgramor could have indirectly caused the collapse, if he summoned/created the Sea-Ghosts. The Sea-Ghosts, with Ysgramor being dead, could have been "triggered" by something at the College (I assume College and not Winterhold because what would it be at Winterhold itself?) or some mage there doing something that ticked them off. Study into souls and soul gems, including the Black Star, could have angered them if they were being harvested. The Augur underneath the College could have caused the Collapse, if he were powerful enough. Perhaps a particularly strong mage there was just messing with high-powered spells and accidentally or purposely summoned a great storm.

In almost any case, I blame the College in one way or another - they directly or indirectly did something to cause the Collapse. Given the lack of talk about it, it was likely known only to the Arch-Mage or perhaps just a particular mage there, if they knew what they were doing. Perhaps it was a rival mage group or a something from the lands of Akavir, but it was more likely a College member at the heart of it.

It doesn't help that, whatever it was, it was not powerful enough to fully pierce the College's protective magic for itself. This could easily point to a lesser mage, especially an advanced College mage that thought they could take revenge or advance spells by conjuring a storm while being oblivious to the amount of power required to actually take down the College itself. I assume that the protection spells on the College were mostly by extremely powerful mages, and that, for instance, Sea-Ghosts or other College mages would not be able to pierce them, but a directed attack from another Mage guild would, if the purpose was to get revenge.