[quote=@Willy Vereb]
Halfway finished with my history section for Yllendthyr.
I started from the prehistoric times and I am now at the early middle ages.
There's just one issue:
I need an enemy.
During the early middle ages the territory what latter be known as Yllendthyr was split into the dominions of 27 warlords.
I need some kind of power which would force them to unite and become the empire we (will) know.

EDIT:
BTW, the best to imagine elves in the early middle ages as the Mongol Empire. They use griffin riders shooting arrows from the skies or deliver massive skydiving charges.
[/quote]

How about the Semids? They're right across the sea, and being elves, would probably have no problem trying to incorporate Yllendtyr into their empire (probably the Kingdom of Sem at that time). I also had an idea of them being historical enemies, with something like a founder myth ala Isaac and Ishmael starting their antipathy, and conflicts only keeping it alive.