The Companions of the Hall was the unofficial name for the adventurers who retook and subsequently defended Mithral Hall. The members consisted of King Bruenor Battlehammer, Drizzt Do'Urden and his companion Guenhwyvar, and Catti-brie, Wulfgar and Regis.
As of 1372 DR, Bruenor, having discovered that what he thought was Gauntlgrym was actually the ruins of Baffenburg, led the political overtures with the fledgling kingdom of Many-Arrows.
Wulfgar then left the group, returning to Icewind Dale to rejoin the Elk Tribe. Cattie-brie gave up the life of the warrior and embraced tutelage from Alustriel in the Art.
In 1385 DR at the beginning of the Spellplague (the time the book The Ghost King took place), Catti-brie was struck by Blue Fire during her meditations and got caught between two planes of existence: the Shadowfell and the Prime Material Plane. Drizzt took her to Mithral Hall where eventually Bruenor and Drizzt took her to Cadderly Bonaduce, with the help of Jarlaxle, through a disguised Athrogate. Drizzt, Bruenor, Jarlaxle and Athrogate teamed up and helped her get to the Spirit Soaring. Once they arrived, they faced the threat of a dracolich calling itself the Ghost King, which was, in fact, a manifestation of the dragon Hephaestus, combined with an illithid and Crenshinibon, the Crystal Shard. Finding the dracolich too powerful, Cadderly sacrificed himself to ward the Ghost King away from the Prime Material Plane forever, but was never fully able to help Catti-brie. Catti-brie eventually died days later in Mithral Hall. With one last goodbye to Drizzt, Mielikki took her away to a private heaven that had been prepared for her and Regis, who was similarly sick from trying to save her with his Ruby pendant, to spend the rest of eternity dancing, completely happy. When Wulfgar died, he too joined them, and fishermen in Icewind Dale reported seeing the three on occasion.
Bruenor spent the last years of his life searching tirelessly for Gauntlgrym with Drizzt, eventually finding it with the help of Jarlaxle and Athrogate. He was infused with the power of ancient dwarven kings before his end which allowed him to go out in a blaze of glory, defeating a pit fiend and saving the Sword Coast North from complete destruction. Before both he and Thibbledorf died of their battle wounds, Bruenor went to live with his children and closest friend in Mielikki's heaven, but Drizzt, still a young man by drow standards, had to forge new alliances and live the rest of his life without his family until the Companions were reincarnated by Mielikki.
One of the most memorable accomplishments of the Companions has been immortalized in Garumn's Gorge. A statue of Bruenor riding the dragon Shimmergloom to its death was sculpted just in time for the signing of the Treaty of Garumn's Gorge.