Grór was a Dwarf who was one of the significant leaders among the people and was the first lord to rule the Iron Hills. Married to Eir, he was the father of Náin III, and grandfather of Dáin Ironfoot. Born in Ered Mithrin as the youngest of three sons born to Dáin I and Heria, his older brothers were Thrór and Frór. After the death of his father in TA 2689, he and his brother left Ered Mithrin. While Thrór went back to Erebor, Grór went further into the east and in TA 2690, he established the Kingdom of the Dwarves in the Iron Hills. Two hundred years later, just before the battle of Khazad-Dûm, he thought himself too old to go, and instead sent his son Náin and grandson Dáin II, the king of the dwarves at the Iron Hills. Despite been old and that Dwarves would live for more than three hundred, Grór still had years to go until he passed away from an unknown cause fourteen years later.
- The Hobbit: An Unexpected Journey (First appearance)