Hador, also called in Sindarin Lórindol (Golden-haired) because he had fair blond hair, was the great-great-grandson of Marach, one of the leaders of the Atanatari, and ruled over the House of Marach, which later also became known as the House of Hador.
Under his rule he and his people swore allegiance to Fingolfin, High King of the Noldor, and he was granted the land Dor-Lómin in Hithlum to live in in the year 423 of the First Age. He also received the Dragon-helm of Telchar, a famed Dwarven-smith from Nogrod, at that time, although none of his descendants would use it in battle. Hador was given this helm because it was made for dwarven-heads, and none had the size to wear it before Hador came: Hador was one of the tallest Men in all of Beleriand.
Hador was slain during the Dagor Bragollach, and the rule of Dor-Lómin passed to his son Galdor.
Hador's grandsons were Húrin and Huor, and Húrin's son Túrin Turambar was the first (and last) heir of Hador who would use the Dragon-helm again.