I was reading up on the elder scrolls the other day and I came to the realization that Alduin, The World Eater, this ancient evil that we are supposed to combat is actually Akatosh an aedra, worshiped by nearly all, a good god. Martin Septim actually became the Avatar of Akatosh at the end of Oblivions main quest and tore Mehrunes Dagon apart to stop the daedric invasion. The question is, why is Akatosh and his kin now destroying Nirn? What has happened that has provoked the wrath of Akatosh, made him 'evil'? I think there is a deeper story to all of this and I am certain that the ending of Skyrim will blow our effin socks off. In the shivering isles we stopped a deity and became a deity but when we 'kill' Akatosh, if we kill Akatosh, what will happen? Really? As dragonborn we will absorb the souls of dragons, minor gods in their own right, so when/if we absorb Akatoshs soul -a major god- will we replace Akatosh and ascend like Tiber Septim? What about the other gods, will they retaliate, will they help? I don't know this game is so crazy, I am really getting into this lol. But yeah I think there is something beyond just some prophecy in the elder scrolls, a reason why Akatosh want to wipe everything away. Any ideas?

where were you 3 months ago, we could have used a man like you back when people were [and many for some reason still are] thinking it was the akaviri who will "dawn with fire"
go look for cipher8's posts. "Dragons" that one has all you need to know.

Because he judges it's time for this Kalpa to reach its end, http://www.imperial-library.info/content/seven-fights-aldudagga
EDIT: Besides, it's only natural that the schizophrenic Time-god would go along this path. He wants it to end so he can begin it again; he wants it to begin so he can end it again.

I think the problem is assuming that the Aedra are on the side of men to begin with. Akatosh stopped Dagon from invading so that he could be the one to destroy it. He's not good, he's not evil. It's about perspective. Men view the Aedra as benevolent and supportive of life and Mundus, elves view the Aedra as trapped in the Mundus. Alduin is destroying it so that he and the other Aedra can be free again.

It is complicated and I would recommend searching around the forums, as it has been discussed in great detail several several times before.

We also won't be killing Alduin/Akatosh. If we did, it would destroy time as we know, undo stability, and the possibility of any future games would be pretty impossible. It would be better to let him eat the world.

It has to have something to do with the civil war. I don't think it just happens that Alduin get's hungry when the Nords are killing their brothers.

We have open discussion for this here:
http://www.gamesas.com/index.php?/topic/1179534-sorry-if-this-has-been-asked-but-i-still-dont-know-if-alduin-is-akatosh/