I remember some friends' of my parents having Fairport Convention's album 'Fairport Nine' , and being fascinated by it as a nipper.
Preceding Fairport's 1975 version, the song has been recorded by Shirley and Dolly Collins, Martin Carthy, amongst others.

One website has traced a published version to 1891.

https://mainlynorfolk.info/martin.ca...ntheshore.html

Song has a strange sense of fatalism, as a young sailor gets pressed into being a privateer.

Great to hear that young folk band 'False Lights' played a version on Radio 2 back in 2014. Other recent versions have been performed by Black Flowers and Bellweather.

False Lights - Polly On The Shore: Live on BBC Radio 2 - YouTube



" Come all you wild young men and a warning take by me
Never lead your single life astray or into bad company
As I myself have done, being all in the month of May
When I, as pressed by a sea captain, a privateer to trade
To the East Indies we were bound to plunder the raging main
And it's many the brave and a galliant ship we sent to a watery grave
Ah, for Freeport we did steer, our provisions to renew
When we did spy a bold man-of-war sailing three feet to our two
Oh, she fired across our bows, "Heave to and don't refuse
Surrender now unto my command or else your lives you'll lose"
And our decks they were sputtered with blood and the cannons did loudly roar
And broadside and broadside a long time we lay till we could fight no more
And a thousand times I wished myself alone, all alone with my Polly on the shore
She's a tall and a slender girl with a dark and a-rolling eye
And here am I, a-bleeding on the deck and for her sweet sake must die
Farewell, my family and my friends, likewise my Polly too
I'd never have crossed the salt sea wide if I'd have been ruled by you
And a thousand times I saw myself again, all alone with my Polly on the shore "