"The Elfin Knight" (Roud 12, Child 2) is a traditional Scottish folk ballad of which there are many versions, all dealing with supernatural occurrences, and the commission to perform impossible tasks.
[2] As is the case with most traditional folk songs, there have been countless completely different versions recorded of the same ballad.
In the oldest extant version of this ballad (circa 1600–1650), an elf is invoked by the wish of a young woman who hears his horn blowing, and he appears at her side and proposes tasks which the lady must perform in order to be accepted as his lover.
Upon her speaking these words, the knight appears, telling her he will marry her if she will perform numerous tasks, all impossible.
In Celtic folklore, in common with many other European traditions, impossible tasks are often given to a suitor as part of a wedding trial – a well known example would be Culhwch and Olwen from Welsh Brittonic tradition where the 40 impossible tasks are set by the father-in-law (in this case the giant Ysbadadden Pen Cawr).
[6] The song "Scarborough Fair" is considered a relatively recent variant of "The Elfin Knight", and both are officially classified as the same ballad.
[7] Mark Anderson (1874–1953), a retired lead-miner from either Newbiggin-by-the-Sea[8] or Middleton-in-Teesdale,[9] County Durham, England, sang "Scarborough Fair" to Ewan MacColl in 1947.
A similar variant is "Whittingham Fair", a song that was popular in the north and west of Northumberland,[11] not far from Mark Anderson's County Durham.
There are also several American variants, which differ greatly, among them "My Father Had an Acre of Land", "The Parsley Vine", and "The Shirt of Lace".