Urthin-Mejin is an Underdark empire spread across Brucrumus's Tier 1 and Tier 2 subterranean areas. In Xalyth, Urthin-Mejin's lands cover much of the same area as the surface empire Angrod. Both of these elven nations, one predominately wood elf and the other drow, have long been enemies. Hostilies were a continuation of the Angrod conflict with the Eldalweril; falling in the High Down War (1285 - 1304). A decade after this conflict, Urthin-Mejin moved in, taking over the lands of the Eldalweril. Urthin-Mejin then captured the former capital of Eldalweril, now a mere city-state, adding Jhaldrym to her holdings.
In the past, Urthin-Mejin has allied with the dragon cult Vith Alok and with the city-state Rumaktharga.