Ysmir Dragon Of The North, one of the gods that the Nords worship. Some believe that he and Talos are the same, but they are not. Ysmir before he was sainted was originally Ysmir Wulfharth of 5 Songs of Wulfharth fame, He was involved with the Numindium which later led to the events of Daggerfell, had an alliance with Tiber Septim which lead to the events of the Numindium occuring because Wulfharth was ticked off at Tiber, and he was involved with Lorkhan's heart to a degree. My theory is that Ysmir will have some form of Impact with Skyrim's story, although I'm not sure if he will be a boss, a Dragon that he will take the spirit of, Lore or some other unknown thing.
Further reading if you aren't sure of what I'm talking about.
http://www.uesp.net/wiki/Lore:Wulfharth
http://www.imperial-library.info/content/oblivion-five-songs-king-wulfharth
http://www.uesp.net/wiki/Lore:Tiber_Septim