St Brynach's Church is situated in a small, polygonal churchyard, which may have originally been curvilinear. It is located some 50m south-west of the Afon Gwaen, raised above the flood plain on a north-facing slope. Two early medieval carved stones (NPRNs 423467 and 304367) stand in the churchyard. The church is some 350m south-east of Castell Caerwen Iron Age enclosure (NPRN 304365) and the two may possibly represent the ecclesiastical and secular components of an early medieval paired site. The church was not a parish church during the post-Conquest period, but was a chapelry of the medieval Deanery of Cemais. It was appurtenant to Pill Priory. At the dissolution, the patronage, along with the appurtenances of Haverfordwest Priory, fell to the Crown. The church had become a parish church by the 17th century. By the later 18th century the patronage had passed to the Laugharne family, and then to the Arden family (who funded restoration work).

The church is a Grade 2 listed building (LB 26809) as a church of medieval origin, forming an historic group with Plas Pontfaen / Pontfaen House (NPRN 30079) and the outbuildings (NPRN 22620). It is constructed predominantly of limestone rubble, and consists of 2-bayed nave, two-bayed chancel, north transept with skew passage, south porch and vestry (between nave and north transept). The nave and chancel are thought to be 13th-century in date. The north transept is thought to date to the 14th century. The limestone font with plain, square bowl, stem and base, is thought to date to the 13th- to 14th-century. The church was noted as disused shortly after 1833, and was a ruin by 1859. The church was restored around 1880, and again in 1901-1904. The porch and vestry were constructed at this time. There are nineteenth century references to oil painting found in church.

Sources include:
Cadw, Listed Buildings Database
Cambria Archaeology, 2000, Pembrokeshire Churches, gazetteer, 48
Cambria Archaeology, 2003, Early Medieval Ecclesiastical Sites Project, Pembrokeshire gazetteer

N Vousden, 23 October 2018