I tried dating songs long ago, but gave up in irritation.

    If it was written in English, it can't be older than 12C. But was the original in English (containing words of French origin) or in Saxon?
    Copyright is no help. People claimed or were credited with songs which predated their birth, sometimes by hundreds of years.

    Many if not most songs have been updated. Hey, they were collected from folksingers!

    On the folk scene, and there are the odd sly ones who can write in a style and then pretend to have 'collected' the song. I suspect that this sometimes starts as a joke, and gets out of hand.


If you should manage a reasonable assumption of age, who are you going to tell? Audiences aren't interested, and other folklorists and musicologists are likely to argue with you. I decided to give up, having reached the point of diminishing returns.
If you should go ahead, you could publish here. Someone could be interested.    Good luck.