Some additional notes of my own gleaned from my research:

The song was collected in Aberdeen in 1792 – and that seems to have been the only time it was ever collected from the oral tradition; although it does form one of the Child Ballads. By the 20th century it seems to have been pretty much forgotten – until in the 1970s it was independently revived, in England by Steeleye Span; and in Scotland by the great traditional singer and Traveller, Lizzie Higgins.

Lizzie Higgins set the original Scots dialect words to a traditional bagpipe tune called “The Bonnie Lass Gan’ to the Fair”. She turned one of the verses into a chorus, and recorded it twice: the first time under the title Alison Gross and the second time with the title Alison Cross. All the Scottish recordings of the song that have ever been made by other people have been based on hers – and several of them are called Alison Cross, because that’s what she called it.

And that’s how folk songs evolve!