Wagner's ring them and Morriconi's "Ecstasy of Gold" (from The Good, the Bad, and the Ugly)

I once heard an old German conductor describe the idea behind the theme of the ring which you hear in Rheingold, e.g. on this youtube sequence starting around 1:50 i.e. a minute and fifty seconds and there's a little timer at the bottom of the thing which ticks off:

The theme is the thing you hear with the single mid-range violin. The conductor described it thus, that the theme ran around in a circle like a ring always coming back to the same point, which was like human greed which never led anybody anywhere other than in vicious circles. That was what the Niebelung's golden ring symbolized in Richard Wagner's conception of the thing. The piece goes to about 240 - 243 on the youtube piece.

What I am convinced of is that Ennio Morricone copied not the music itself but the basic idea behind it for his "Ecstasy of Gold" piece in Sergio Leone's "The Good, The Bad, and The Ugly", which is likely to achieve immortality as the all-time ultimate western. The scene shows Tuco (Eli Wallach) running in a circle in a circular grave yard until his path finally blurs into a ring of sorts, looking for the one grave with the federal gold shipment.

Try watching the two pieces and see if you can't see the relationship.