from what i've heard the timeline of the game is taking place a couple hundred years before End Times. i guess thats the "history" aspect for the Total War side of things! lol
if you've played and enjoyed any Total War game and you happen to be a Warhammer fan this is exciting. Im interested to see how they are going to design the Campaign portion of the game. Thats probably why the game is taking place before End Times so they can use the Old World as the setting for the campaign map as opposed to these "bubbles" of reality.