Tradition holds that following the Roman departure, Roman customs held on into the 5th century in southern Wales, and that is true in part. Caerwent continued to be occupied, while Carmarthen was probably abandoned in the late 4th century. In addition, southwestern Wales was the tribal territory of the Demetae, who had never become thoroughly Romanised. An influx of settlers from southeastern Ireland had taken place in the late 4th century, both in northern Wales and in the entire region of southern and southwestern Wales under circumstances that are still poorly understood, and it seems far-fetched to suggest that they were ever Romanised.