Nordri

Nordri son of Gorin, is the Lord of Nordinbad during the Fourth Age, it is unknown wether he had any children of his own. So lordship of Ered Mithrin might've passed down to one of his loyal officers or some noble-dwarf of Erebor.

History
Nordri was born in the later years of the Third Age, and is next-in-line to the throne of Nordinbad. During the War of the Ring, Nordri's people were threatened by a Black Numenorean named Agandaur, a dark sorcerer and the right hand of the dark lord, Sauron. Agandaur came to Nordinbad under parley, and demanded that Nordri and Gorin turn over Nordinbad to him and his army, and if they do, their lives would be spared and they could seek out a new home. Of course, Nordri's father refused, and in his wrath, Agandaur warned them that for their defiance, a fiery doom will come upon them and destroy them all.

Afterward, Nordri leads a mission to reactivate an ancient weapon within the Orc-infested peak of Mount Gundabad, with the knowledge that they would surely die. Accompanied by his friend Bruni, Nordri and his companions fought through many orcs, as well as Mountain-trolls and Uruk-hai. Only Bruni and himself eventually made it to the chamber of the weapon, where they were surrounded by a horde of enemies. As they made ready to fight to the end, three strange warriors - Eradan of the Dunedain, Andriel of Rivendell, and Farin of the Lonely Mountain - arrived to their aid, and drove the enemy wave back. Nordri told them of their plan to activate the weapon and crush the orcs, to which they agreed to safeguard them while they activate it. After waves of enemies repeatedly attacked them, Nordri and Bruni eventually activated the weapon, which brought the whole mountain down upon the orcs, and they would eventually be brought down with it. Nordri apologized to the three heroes for getting them killed with them, but in that moment, three Great Eagles flew into the mountain and flew them out before the mountain collapsed upon them.

When they returned to Nordinbad, Nordri introduced the three heroes to his father, who thanked him for bringing Nordri back alive and for saving their home. Eradan, Farin and Andriel then tell them they had gone to Gundabad in search of Agandaur, and Nordri and Gorin told them about their meeting with him. When they mention his warning of the "fiery doom," they fear that Agandaur had allied himself with Urgost, a dragon who lives farther east. Nonetheless, the heroes agree to go after the dragon, and Nordri mentions that they can find Urgost's dwelling with help from Radagast the Brown, who dwells in the forests of Mirkwood.

After Farin, Eradan and Andriel leave to find Radagast and locate Urgost, Agandaur had once again plotted against Nordinbad. The dark servant of Sauron had unleashed an immense army of Orcs, Uruk-hai, Goblins, Olog-hai and Men of Carn Dum. They had launched catapults upon them and amassed siege towers on the walls, and in the chaos, Bruni was killed. Farin, Andriel and Eradan returned from Urgost's lair to aid Nordri and his kinsmen, telling them to go back inside the mountain and defend the rest of their people. The heroes were able to drive back waves of enemies, but their eagle companion, Beleram, had been gravely injured, whilst Baranthor and Armenel had been killed. When the battle had ended, Nordri promised the heroes that Beleram would have the best care they could give Beleram.

Nordri and his people survived the bloody siege, but at the cost of so many kinsmen. Long after the three heroes left for Carn Dum to finish off Agandaur, Beleram had left the dwarves' care to go and aid his allies.

Fourth Age
After Agandaur's defeat and the destruction of Sauron, the Fourth Age of Middle-Earth had begun. Nordri and his fellow dwarves rebuilt Nordinbad. It was also later revealed that Farin had told Gloin, a fellow Longbeard, the existence of Nordinbad, and that he would be happy to establish trade between them and the dwarves of Erebor, now ruled by King Thorin Stonehelm. In later years, Gorin had past the lordship of Nordinbad down to Nordri, and he ruled with good cause and utter surety.