In Wagner's opera Der Ring des Nibelungen, based on the Germanic epic poem Nibelungenlied, Rhinemaidens guard the Rhinegold, of which anyone who first renounces love can make out a magic ring, which will let its bearer rule the World. Alberich, a Nibelung dwarf, steals the gold and makes the legendary magic (and cursed) ring out of it.
In Nibelheim, Alberich enslaved the rest of the Nibelung dwarves. He forced his brother Mime, the most skillful smith, to create a magic helmet, the Tarnhelm. Alberich demonstrates the Tarnhelm's power by making himself invisible, the better to torment his subjects. This is when several mythic figures struggle for possession of the Ring, including Wotan (Odin), the chief of the Gods. It will lead to their doom...
The link with Tolkien's trilogy is obvious. The idea of the cursed ring of power that everyone craves to control, the magic, the giants, the dwarves, the Valkyries (the Elves in LotR), and even the magic helmet (which has become a cloak in LotR) comes from the Nibelungen.
Interestingly, the Nibelungs (or Niflungs) are linked in Germanic literature to be the Burgundians, a Germanic tribe originally from the island of Bornholm in Denmark, who lived around Worms (Rhineland-Palatinate, Germany) at the time of the story. They seized the Eastern part of Roman Gaul in the 5th century and settled to this day in what is now Burgundy, Franche-Comté and French-speaking Switzerland.
Germanic-type inhabitants of this region are thus the descendents of the legendary Nibelung dwarves who stole the Rhinegold to make the ring of power. Maybe that is why Francophone Switzerland has such a long tradition in jewelery making.
And, who knows, the ring might still be hidden somewhere in the mountains of Switzerland, which is why the Swiss are so rich and so keen to remain independent and neutral in world affairs, so that nobody finds out...
In Nibelheim, Alberich enslaved the rest of the Nibelung dwarves. He forced his brother Mime, the most skillful smith, to create a magic helmet, the Tarnhelm. Alberich demonstrates the Tarnhelm's power by making himself invisible, the better to torment his subjects. This is when several mythic figures struggle for possession of the Ring, including Wotan (Odin), the chief of the Gods. It will lead to their doom...
The link with Tolkien's trilogy is obvious. The idea of the cursed ring of power that everyone craves to control, the magic, the giants, the dwarves, the Valkyries (the Elves in LotR), and even the magic helmet (which has become a cloak in LotR) comes from the Nibelungen.
Interestingly, the Nibelungs (or Niflungs) are linked in Germanic literature to be the Burgundians, a Germanic tribe originally from the island of Bornholm in Denmark, who lived around Worms (Rhineland-Palatinate, Germany) at the time of the story. They seized the Eastern part of Roman Gaul in the 5th century and settled to this day in what is now Burgundy, Franche-Comté and French-speaking Switzerland.
Germanic-type inhabitants of this region are thus the descendents of the legendary Nibelung dwarves who stole the Rhinegold to make the ring of power. Maybe that is why Francophone Switzerland has such a long tradition in jewelery making.
And, who knows, the ring might still be hidden somewhere in the mountains of Switzerland, which is why the Swiss are so rich and so keen to remain independent and neutral in world affairs, so that nobody finds out... 
