In 1868, the parish of Cwm contained the following places:
"CWM, a parish in the hundred of Rhuddlan, in the county of Flint, 2 miles N.E. of St. Asaph. It contains the townships of Cwm-Isglan and Uchglan. It is situated in a pleasant valley, as its name, Cwm, or Coombe, signifies. The inhabitants are chiefly engaged in the iron-works. The living is a vicarage* in the diocese of St. Asaph, val£300, in the patronage of the Bishop of Llandaff. The church is dedicated to St. Valacinian. The charities amount to £17 per annum."