User blog comment:Fimmion/Why Skyrim was rigged from the start/@comment-5191171-20120630141210/@comment-1727531-20120701055404

Imperium was weak due to oblivion crisis and fighting for who will take over as emp.

Thalmor sucker punched the empire by rushing through valenwood and elswyre both of whom they took... Conquered valenwood and elswyre joined them in return for the thalmor fixing the moon.

Legions took heavy hits early on and were in shambles. Emperor rallied the troops and pulled back consolidating then pushed back. Problem is too many troops were lost. Empire agreed to concondant because humans have far faster birthrate and can therefore replenish faster than the thalmor.

I do agree the septims were better though - compare the imperial legion armor from oblivion and skyrim ...