Revenge of the Giants
The Empire of Nerath lasted for several hundred years. It came after the fall of Bael Turath and Arkhosia, which tore each other apart “many centuries ago” and Nerath wasn’t established until sometime after that. Up until four centuries ago the Nentir Vale was ruled by human hill-chieftains, but then settlers from Nerath in the south began moving north into the vale. Nerath is somewhere in the neighborhood of 500 years old, and it fell almost 100 years ago in a war with the gnolls under the banner of their demon god the Ruler of Ruin.
Nerath was predominantly a human kingdom, but in those ancient times its citizens allied to form the Empire. Other races, though civilized and good as any human nation are largely marginalized and considered monsters because they weren’t part of this once great nation.
Most of the cities and Points of Light that exist in the world were once part of Nerath. The roads that still exist were created by them, as are most of the castles and keeps (though many lie in ruins after the war). With the fall of Nerath, many races pulled back to their homelands, the elves to the forests, the eladrin to the Feywild, the dwarves into the mountain valleys, but strong ties of fellowship and long traditions still remembered connect them. In some places, life continues on much as it did during the days of the Empire.