Nár was an old Dwarf, the sole companion of King Thrór when he set out to wander in the wilds of Middle-earth. The journey of Thrór and Nár eventually brought them to the old dwarf-halls of Moria, now infested with Orcs and Trolls. Disregarding the pleas of Nár, Thrór insisted on entering Khazad-dûm.
That was the last any Dwarf ever saw Thrór alive. He was beheaded by the Orcs, and their leader Azog branded his own name on Thrór's brow. The Orcs allowed Nár to return to Thrór's son Thráin, with a message that Azog now ruled in Moria, but this proved to be a terrible mistake. Nár's message raised such anger that it sparked the War of the Dwarves and Orcs, and in the climactic Battle of Azanulbizar, Azog himself was slain along with countless others on both sides.