Dafydd y Garreg Wen is a traditional Welsh musical air and folk song.
There is a tradition that as Owen lay on his death bed, he called for his harp and composed the tune of the haunting song.
[1] The first printed appearance of the melody is in Edward Jones's Musical and Poetical Relicks of the Welsh Bards (1784) The words were added more than a hundred years later by the poet John Ceiriog Hughes (1832–1887).
Mostyn Thomas opened the programme, singing Dafydd y Garreg Wen, and so it became the very first Welsh language song to be played on the air.
[2] An arrangement for military massed bands is played annually during the national remembrance Sunday celebrations led by His Majesty the King each November in Whitehall.