Treuddyn is regarded as being one of the ancient parishes of Flintshire; although it was a chapelry of the parish of Mold until 27 May 1844. On that date, it officially became a separate parish. In practice, Treuddyn had long operated as a separate parish, although it was held jointly with Nercwys until 1832.
The old church had fallen into a dilapidated and insecure condition, and was demolished in 1874. A new building was erected on the same site, and was opened on 5 August 1875.
For family history information about the church and parish, visit the GenUKI Treuddyn page.