Looks like many of us have been giving credit for St. Denio to the wrong composer for many years. According to the Dictionary of Welsh Biography (http://yba.llgc.org.uk/en/s-ROBE-JOH-1807.html), the actual composer is a different John Roberts (1807-1876).
This solves a long standing mystery on how John Roberts (1822-1877) could have published Caniadau y Cysegr in 1839, when he would have been only 17 years old.
Comments
Good job!
He joins the Johns Newton!
ST DENIO
Thanks, I corrected all the instances that did not specify the dates 1822-1877.