Sone interesting thoughts here. And some helpful feedback. I'll follow up the leads offered and hopefully I'll discover some good evocative songs.

I suppose I hadn't even considered exactly what 'pagan song' is, except for the fact that they were described to me as such by the friend who sung them!

Insane Beard, you make some interesting comments. By 'truly pagan' you seem to be describing a more cthonic sound evoking perennial mythic themes? Loved Shibboleth BTW, though I'd have a hard time trying to sing it! The way I read you, it sounds like your saying something may be described as 'truly pagan', where 'pagan' is functioning more as a verb than a noun. The same might of course be argued of Robert Graves himself, an inspired poet, doing creatively what all good Druids are supposed to do..