Kertwald Plain was the site of the “final battle” between the Horde and the forces of men. This is where the PCs woke up at the start of the campaign. It is situated in the Eastern hills of Adlerreich, a few days’ journey from the Hohlberg mountains.
Allegedly the battle took place about three months before the start of the campaign, but the PCs noted that the state of the bodies on the battlefield did not suggest that they had been there for more than a few days at most.
The PCs also noted that there did not appear to be any demon corpses on the battlefield; just human ones.