 Although Jersey was part of the Roman world, there is a lack of evidence to give a better understanding of the island during the Gallo-Roman and early Middle Ages.The tradition that the island was called "Caesarea" by the Romans appears to have no basis in fact.The Roman name for the Channel Islands was "I. Lenuri" (Lenur Islands) and were occupied by the Britons during their migration to Brittany (5th-6th century).