"I Am Stretched on Your Grave" is a translation of an anonymous 17th-century Irish poem titled "Táim sínte ar do thuama" It was translated into English several times, most notably by Frank O'Connor. It was put to music by musician Philip King in 1979.
It is set to the tune of "Taim Sinte ar do Thuamba", Hymn #47 in Danta De: Idir Sean agus Nuad (the Trinity Sunday hymn "Dia an t-Athair do shealbhaig flaitheas naomhtha"). The hymnal says the tune is from Munster. (from Wikipedia)
Kate Rusby is one of my favorite singers. She comes from Barnsley, Yorkshire, England and is one of the most noted contemporary folksingers.