Durin IV
Tolkien records nothing of his reign. He would have lived in Khazad-dûm in the late Second or early Third Age.
A persistent rumour on the Web holds that Durin IV was the king who led the Dwarves from Khazad-dûm to fight against Sauron with the Last Alliance at the end of the Second Age. Tolkien indicates that Dwarves of Durin's Folk did fight with the Last Alliance, but he does not say under which king they fought.
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