St Edeyrn's is one of a number of ancient Christian sites which were established soon after the founding of Llandaff Cathedral, as the Celtic church was anxious to spread itself through the region as swiftly as possible in order to secure its position.

After the Norman Conquest, the church was rebuilt and became a chapel of ease to St Mary's.

In the 12th century, it was recognised as the property of Tewkesbury Abbey, but was transferred to the Bishop of Llandaff in 1236, at which time it became a separate parish church.

An extensive restoration occurred in 1888[2] when the east chancel wall was completely rebuilt.

[3] The church gained listed status in 1963,[4] after which the machine-made tiles of the roof were replaced with Welsh slate.