"Cilcain is a very ancient village, lying beneth Moel Fammau, the highest of the Clwydian Hills. ... This village lies in the midst, and commands an extensive range, of most beautiful scenery. The cottages and farmhouses are nearly all whitewashed or coloured, and look exceedingly picturesque."
[From Handy Guide to Mold and the Neighbourhood , Tweddel, 1890]
Cilcain is one of the "ancient parishes" of Flintshire. It originally comprised the seven townships of Cefn, Llan (or Tre'r Llan), Llystynhunydd (or Glust), Llys y Coed, Maes y Groes, Mechlas (or Dolfechlas), and Trellyniau.
On 27 June 1848, the township of Trellyniau and part of the township of Llystynhunydd went to the new parish of Rhesycae.
On 31 March 1865, the remainder of Llystynhunydd, and parts of the townships of Cefn and Mechlas went to the new parish of Rhydymwyn.