[@Musaki Hajime] From what I can tell, it's the 'long time ago in a land far, far away' thing. Set on the other side of the globe, and apparently at a time where Valkyrur were more common (they litterally have a unit devoted to hunting them), it's probably set long before the whole 'darcsen calamity' and conquest of europa by the valkyrur. I guess that's how they explain it all away? Magical properties of ragnite, the knowledge of which has been lost to the ages (sorta like greek fire). 

Either way, I'm not a huge fan. Especially because instead of fighting on the side of the REDICULOUSLY TECHNOLOGICALLY ADVANCED NATION with GUNS and HUGE MECHS, you get to work with swords, magic and the occational bolt action rifle... I really want a game set the other way some time. Fighting magicians with glorious ballistic weapons and human technology.