In the received history of Britain in the fourth century, a special place is occupied by the Saxons. It is asserted that the defensive system of the Saxon Shore existed to prevent them from landing; and it would seem that, unlike any of the barbarian tribes with whom Rome maintained uneasy relations along the Rhine and the Danube, unlike even the Goths, the possibility of their peaceful settlement within the boundaries of the most accessible Roman province could not be entertained. Their attacks, apparently, were so unpredictable, and their nature so savage, that in this case alone the policy of the Roman authorities was one of total exclusion. In 367, moreover, after forming an alliance with the tribes of the north and the west, they overwhelmed the Roman defences and ravaged Britain; and this date has been accorded the status of a turning-point in fourth-century history. But afterwards the Saxon Shore forts resumed their function of keeping the Saxons out. Finally, the Roman garrison was withdrawn and the Shore forts abandoned; and this permits historians to assign an early fifth-century date to the beginning of the Anglo-Saxon settlement.