Maryrrf---songs can go back over eons. One thing can be said; Samuel Pepys, the English diarist of the 1600s mentions having heard "Barbara Allen" in Scotland. Strangely, the closest version I ever heard to the Scottish one I was brought up with was one I heard Nic Jones sing 'way back in the mid-60s. [Nic did tend to sing much undeniably Scottish material, mind you---"Lochmaben Harper"etc. Perhaps he had actually chosen to sing that version.]