The Reach is, very roughly speaking, the territory or sphere of influence surrounding a Nonman Mansion. The Nonmen did not place the same value on holding territory for its own sake that men later did, but did place a value on holding areas of interest or containing resources that were useful.
Many of the smaller Mansions had most Reaches restricted to the immediate vicinity of the Mansion. However, the Nine Great Mansions had considerably larger Reaches stretching across hundreds or even thousands of miles.
The greatest Reach in history was that of Cû’jara-Cinmoi, the King of Siöl. At the height of his power he controlled Siöl, Viri, Nihrimsul and Cil-Aujas and their combined Reaches. This created a land empire stretching from the northern Great Kayarsus west and north to the Yimaleti Mountains, south to the Sea of Meneanor and west to the Demua Mountains. This may be the largest land empire in the histoy of Eärwa, although far less populous than later empires of men.
Following the Breaking of the Gates and the resulting Cûno-Halaroi Wars, all of the Mansions and their Reaches were overrun and lost. The sole exception is Ishterebinth, which controls a Reach known as Injor-Niyas.