Board Thread:Lore Discussion/@comment-25196161-20140718180949/@comment-69.123.217.197-20150210212435

Tiber Septim wasn't a general per se, they were generals. Hjalti, Wulfharth, and Zurin didn't become the singular entity Talos until they ascended to godhood. And of course, it didn't hurt that Hjalti Early-Beard had the Thu'um, one of the most powerful battlemages of the era, and a pissed-off ash storm flying above his head.

As for the Last Dragonborn, consider the fact that soul stacking is one of the Walking Ways to divinity, and that he/she has the opportunity to eat literally hundreds or thousands of dragons, each of whom could have eaten any number of other dragons themselves. What you get is an incredibly massive shard of the Time Dragon, certainly the largest that is physically on Nirn. I would argue that the Last Dragonborn, if anything, would achieve apotheosis by virtue of this fact: perhaps making Ysmir less of a ceremonial title and an actual Dragon (god) of the North.