Ulwarth was an Easterling who lived during the First Age, and the son of Ulfang the Black. With his father and his brothers, Uldor the Accursed and Ulfast, he swore an oath of allegiance to Caranthir, the son of Fëanor.

But Ulwarth, his father, and his brothers betrayed Caranthir during the Nirnaeth Arnoediad. Although he was slain by the sons of Bór, the betrayal of Ulwarth and his kin led to the victory of Morgoth and the defeat of the Elven armies.
Encyclopedia entry originally written by NellasTaralom