The song was written by Ken Stephens from Southampton who has written many fine songs. I believe he was inspired to write this after seeing a programme about the evacuation of St Kilda.
Alan and I were lucky enough to learn it many years ago at a Whittlebury song and ale event - back in the 1980's I think. It has always been a favourite. Nice to bump into Duncan in Portree at the end of August when he told us he had been able to sing it on Hirta during his visit.. Back from whence it came!