The records of individual ecclesiastical parishes include registers of baptisms, marriages and burials, as well as records of the churchwardens and Parochial Church Councils, parish charities, schools, clubs and societies.
Parish records were deposited at the Clwyd Record Office, following an agreement of 1976 between the Church in Wales and the Welsh County Councils.
The ancient parish of Ruthin contained the two townships of Cae'rfallen and Tre'rcastell. Ruthin Church was originally a chapel-of-ease under the Mother Church of Llanrhydd. It is dedicated to St. Peter, and was built and endowed in 1310 by John, son of Reginald de Grey, who also provided a suitable dwelling-place for seven priests, who were to serve the church and live in community upon its revenues.
The original building consisted of two churches, side by side, one for the parishioners, the other for the monastic priests. For this reason it was and still is frequently called "The Collegiate and Parochial Church of St. Peter." The College being dissolved at the Reformation, the collegiate church fell into decay and finally was almost completely demolished. The church was extensively restored between 1854 and 1859, during which period a lofty spire was added to the tower. It was re-opened on All Saint's day, 1859.
[Information taken from http://www.genuki.org.uk/big/wal/DEN/Ruthin/index.html (last accessed July 2015)]