The Wainriders, the Balchoth and the Easterlings of the Third Age all rode out of Rhûn. Their camp at the Morannon is the first piece of the East we've built. The Sea of Rhûn and the lands beyond it are still to come.
Rhûn
The wide East beyond the inland sea — Easterling kingdoms of horse and wagon that have hammered at Gondor's borders for two thousand years.
Coming soon
East of Mordor and Mirkwood lies Rhûn, home of the Easterlings and sworn to the Dark Lord. Our first glimpse of its armies has already marched west: a war-camp at the Black Gate.