User blog comment:Kickratgames1101/Beorn Speculation/@comment-25754873-20180415160400

Khazad-dum was founded thousands of years before Men even awoke, also the Men of the Vales of Anduin(along with apparently the rest of the Northmen) all held the King of Gondor as there overlord.

Hobit, Chief of the Inquisition (Inform me of heretics)