"A parochial chapelry, in the parish of Holt, Union of Wrexham, hundred of Bromfield, county of Denbigh; 5 miles (E) from Wrexham." [A Topographical Dictionary of Wales, 1833 & 1849, Samuel Lewis]
Until 1827, Isycoed was a sub-chapelry of Holt, which was itself a chapelry of Gresford.
In 1827, Isycoed became a separate parish, with an area of 3530 acres, comprising the townships of Cacca Dutton, Dutton Diffaeth, Dutton y Bran, Ridley, and Sutton. Although the parish of Gresford was (and still is) in the diocese of St. Asaph, Isycoed was in the diocese of Chester until 1849, when it was transferred to St. Asaph.
The parish of Isycoed should not be confused with the Flintshire parish of Bangor Isycoed, which lies a few miles to the south, nor with the Flintshire (Maelor Saesneg) parish of Iscoyd (also known as Whitewell).
They are three quite distinct and separate parishes.