From the back of the box set:
Between East and West, between Earth and Sky, lies the Endless Waste. Barren and desolate, this windswept land forms the barrier between the feuding kingdoms of Faerun and the ancient empires of Kara-Tur. The eternal steppe is home only to the hardy, nomadic horsemen who travel its secret paths.
This region, long ignored by its neighbors, is about to erupt in the bloodiest conflict ever to sweep across the Forgotten Realms. Yamun Khahan, Emperor of the Tuigan, has united the barbarian tribes into an unstoppable horde. Already he rules the steppes, from the Cave of a Thousand Gods to the Valley of the Dog-Men. Driven to conquer, Yamun Khahan looks both east and west, and sees a world ripe for the harvest.
THE HORDE Campaign Set includes:
Two 64-page encylopedias describing the Endless Wastes and the barbarians who live there;
Four full-color maps, showing the Endless Waste from Rashemen and Thay in the west to Shou Lung in the east, plus the Caliphate of Semphar and many other locales;
Eight pages of monster descriptions ready to be added to your Mostrous Compendium;
Twenty-four individual hand-outs with adventure information, background on the region, and illustrations of the nomadic barbarians;
A clear plastic measuring overlay.