"A parish in the Union of Ruthin, partly in the hundred of Maelor, county of Flint, but chiefly in that of Yale, county of Denbigh; 4½ miles (E by S) from Ruthin, containing 1475 inhabitants. The village is pleasantly situated on the river Alyn. ..... Throughout the vale in which the village is situated, and on every neighbouring eminence, are numerous tumuli, of which several have been opened at various times, and found to contain sepulchral urns filled with ashes, with human bones, which had resisted the action of the fire, scattered about them in profusion." [A Topographical Dictionary of Wales, 1833 & 1849, Samuel Lewis]
The ancient parish comprised the township of Bodidris (in Flintshire), and the Denbighshire townships of Bodigre yr Iarll, Bodigre yr Abbot, Chwileriog, Gelligynan, Creigiog Uwch Glan, Creigiog Isglan, Alltgymbyd, Trellan, Banhadlen, Cyfnant, Gwaunyffynnon, and Erryrys; with a total area of 11,651 acres.
However, portions of Erryrys, Cyfnant and Gwaunyffynnon went to the newly created parish of Eryrys in 1861.
By an Order in Council, gazetted on 11 March 1887, part of the parish of Llanarmon yn Iâl was transferred to the parish of Llandegla. Archdeacon Thomas defines the area transferred thus :
"That portion of Llanarmon lying south of a line drawn from Pont Ystyllod through Rhos Isa and Perthichwareu, and taking in also a portion of Bodidris township (including the Hall)and the Gwernoliaid, as far as Llyn Maelor."