User blog comment:G0LD3NF1RE/Skyrim Dawnguard DLC/@comment-138.87.179.41-20120502222942

May be nothing, but in the book 'The Great War' in-game, there is reference to the Thalmor using the lost 'Dawn Magicks' to control the moons Masser and Secunda. Perhaps that is just a trivial fact, though. There is a lot to support the Thalmor being involved, whatever the case.