Vaughan Williams collected a wonderfully incongruous tune from a Buckinghamshire tailor , Mr Wetherill. It has only a vestigial text, but the lyric from Motherwell's Minstrelsy fits it beautifully.
It's great to sing because it is such a bouncy tune, and such a contrast to the tragic story.
You can find it in 'Folk Songs Collected by Ralph Vaughan Williams' edited by Roy Palmer, printed by Dent 1983.
Mary Humphreys