I always thought lilting arose from all these destitute Scots & Irish unable to afford instruments and making up for the lack. ...but anyways - try checking out a track by Joe Heaney (Seosamh o hEanai - forgive the lack of fadas) called 'Diderumdoda' (I think). It's on an LP called 'Come all you Gallant Irishmen' (and possibly other compilations of his stuff). He leads into the lilting with a wee story that gives a sort of spoof background to lilting