The Llangwm History Society has received a Heritage grant to research the Flemish settlement of South Pembrokeshire and restore St. Jerome’s Church. The church was built towards the end of the 12th century by Flemish craftsmen and funded by the De la Roche family.
Part of the project involved DNA testing of seven men from the community who could trace an unbroken male line for the last 250 years. The work was done in association with the Welsh TV Channel S4C and DNA Cymru. The DNA results are mentioned in episode 4 of the TV program and it can viewed via this link. The program is in Welsh and you must turn on the English subtitles in the audio section (DNA results are mentioned at the 41 minute mark).
One of the seven men was a Roach and the DNA results indicated that he belongs to the main ancestral lineage in the Roche DNA Project (lineage #1). DNA Cymru have stated that this result links the Irish and Pembrokeshire families which descend from the original founder, Godebert the Fleming.
Further details of the Heritage Llangwm Project can be found on their website.