nedjer
Adventurer
A look at the door to Moria indicates that Tolkien was well-versed in the Christian esotericism associated with Art Nouveau, the Arts and Crafts movement and the Celtic Revival. Perhaps unsurprising that he came up with a story involving a quest, various way-stations and popping into the under/ otherworld.
He also had access to Victorian and Edwardian mash-ups of history and folklore which mixed formative archaeology with much older symbolic texts. That allowed him to draw widely on legend and folklore, but without situating much of it.
Apparently, Orkney was seen as fascinating because the Picts were considered as a bit scary, a bit fey, and a bit lurking in the mist. And, at a time when Tutankhamun's tomb had triggered huge interest in tombs and treasures, the recently investigated Neolithic monuments on Orkney were labelled tombs and seen as part of a contiguous tradition. In amongst that are Norse/ North European traditions such as the duergar. Tolkien had no end of sources around him.
He also had access to Victorian and Edwardian mash-ups of history and folklore which mixed formative archaeology with much older symbolic texts. That allowed him to draw widely on legend and folklore, but without situating much of it.
Apparently, Orkney was seen as fascinating because the Picts were considered as a bit scary, a bit fey, and a bit lurking in the mist. And, at a time when Tutankhamun's tomb had triggered huge interest in tombs and treasures, the recently investigated Neolithic monuments on Orkney were labelled tombs and seen as part of a contiguous tradition. In amongst that are Norse/ North European traditions such as the duergar. Tolkien had no end of sources around him.