Evan Morgan (b. Tyn-dre, Morfa Bychan, Wales, 1846; d. Portmadoc, Wales, 1920) was a furniture maker by trade in Morfa Bychan in the Lleyn Peninsula. He took an interest in music at a young age, however, and became well-known in Wales as a singer and poet. He composed some hymn tunes and arranged folk tunes for the brass band in Portmadoc. His tune TYDDYN LLWYN was first published in the second appendix (1890) to Ieuan Gwyllt's Llyfr Tonau Cynulleidfaol (The Book of Congregational Tunes, 1859). The tune's phrases balance each other very well; the final phrase resolves the rhythmic energy and harmonic color of the initial lines. Part singing goes well with a moderate tempo.
--Psalter Hymnal Handbook
TYDDYN LLWYN is given in the 1995 Welsh and English Hymns and Anthems (Reformatted) of the (US) Welsh National Gymanfa Ganu Association, Inc., with a three-stanza Welsh text beginning "Ti yr hwn wrandewi weddi" and a five-stanza English text of God of grace and God of glory (differing slightly in a couple of places from the text linked to).