Song in town?

From 01:04:45 to cca. 01:06:04, when the brothers and Anne enter a town together with a company of withdrawn Confederate soldiers, a folk-like song can be heard very quietly in the background. (If I try to increase the volume, the hoofbeats and talking become overwhelmingly loud.) I'm not sure but maybe it begins with the words "Quando sei ... mio" and seems to be sung by a wonderful female voice (plus male choir) in Italian, although the style is more Spanish. Does anybody know this song and the performer? Was this also written by Nora Orlandi (as there is no other composer credited) or did they simply borrow it?