Hughes was born in Dowlais, and brought up in Llanilltud Faerdref (in English: Llantwit Fardre), Pontypridd.
[6] Cwm Rhondda was put to words of William Williams 'Arglwydd arwain trwy'r anialwch' which translated as Guide me, O thou great Redeemer, one of the most celebrated of Welsh hymns it continues 'pilgrims through this barren land', referring to the plight of the Children of Israel condemned to wander in the desert wilderness.
Popular in Welsh chapels, it became widely used in English services, and is still recalled to this day as one of the best church anthems.
As described by William Jensen Reynolds, Hughes worked his entire life in secular jobs, his worldwide fame as a composer of hymn tunes being the result of a hobby he pursued on the side.
Like his father, who had profound effect on him, Hughes participated actively as member and deacon in Tonteg's Salem Baptist Church.