Horse-lords of Rohan details the Rohirrim, describing their history and their lands, as well as introducing rules for two new cultures, the Riders of Rohan and the Dunlendings. Also included are rules for handling horses, riding in combat and horse-breeding. As well as the lands of Rohan, this supplement also details the ancient Forest of Fangorn, shedding light on its mysterious inhabitants, the Ents and terrible Huorns; the folk of the Dunland Fells; and the Tower of Isengard and the machinations of the White Wizard, Saruman. It is an indispensable resource for Loremasters looking to take their game into a whole new region.