Tolkien and Wagner?

[Gayalondiel]

Can anyone tell me if Tolkien had an interest in Germanic mythology? I ask because I recently bought Wagner's Ring des Nibelungen and I found lots of similarities:

1) A Ring of power. (cunningly enough)
2) The dwarf in Seigfried is called Mime, isn't there a dwarf called Mim somewhere in the Silm?
3) Seigfried's sword is forged from the shards of his father's.
4) Brunnhilde's father decrees that no man should marry her unless he be great enough to pass the obstacles guarding her (that's sort of the same)
5) Brunnhilde falls in love with Seigfried and renounces her immortality
6) Aforementioned father is of the race of gods on earth. Whose power is waning and they are departing from the earth.

I thought that was all a bit much for coincidence, unfortunately i don't know any of the background mythology. Are these all common elements or am i seeing things? [img]smilies/cool.gif[/img]