What is the name of the goblin king who forged the Sword of Gryffindor?

The goblin king who forged the Sword of Gryffindor was Ragnuk the First.

The sword was made about a thousand years ago to Godric Gryffindor’s specifications. Ragnuk was described as the finest of the goblin silversmiths, and in goblin culture the king was expected to be the most skilful worker rather than someone who simply delegated the craft. The weapon was fashioned from pure silver and decorated with rubies, including stones associated with Gryffindor House.

After completing the sword, Ragnuk coveted it and tried to reclaim it. He claimed that Gryffindor had stolen it and sent goblins to take it back. Gryffindor defeated the attackers with magic but spared their lives, sending them back with a warning. Ragnuk ultimately left the sword with Gryffindor, although some goblins continued to tell the story as a theft.

This history explains why the sword has a disputed ownership story. Wizarding tradition treats it as Gryffindor’s sword, while goblin tradition remembers Ragnuk as its maker and original rightful owner.