Spoilers Ahead!
Be warned! This article contains spoilers!
Hrothgar was the forty-second dwarf king, the leader controlling the thirteen dwarf clans. He held this position for more than a century, and was considered ancient even by the dwarves.
As king, he was directly in charge of the Clan of Master Smiths and Metalworkers, the Dûrgrimst Ingeitum, and simultaneously ruled the twelve other clans as well, although he also gave jurisdiction to leaders under him.
History
Little was revealed concerning Hrothgar's past. He had faith in Ajihad, leader of the Varden, and managed to uphold an alliance between the humans and dwarves. After Orik's parents died, Hrothgar took him in and made Orik his heir. He also honored Eragon by bestowing upon him membership in the Dûrgrimst Ingeitum. He and the Dwarves under him fought alongside the Varden in the Battle of The Burning Plains. Although he fought valiantly, he was subsequently slain by Murtagh. This was a double tragedy for the Dwarves, because Hrothgar had wished to die facing a foe in melee combat, not a cowardly magic user.
- In the movie, Hrothgar is portrayed as normal size, but dwarves are really a few feet smaller than humans.