At Lymne early inscriptions, etc. have been found built into the walls, indicating a period if not late in the Roman period, at least a considerable time after the date of the inscribed stones which were enclosed, as mere building material, in the walls. This is corroborated by indications of adhering barnacles, from which we may fairly conclude that there was a period of submergence between the time of the carving and the subsequent use as building material.
It seems probable, therefore, that although the earlier fortresses may have been intended to serve as centres for the Roman army, they may have been supplemented at a later period by other castra, forming altogether a chain of defences intended to protect the shores of Britain against Saxon invaders.
The late Mr. G. E. Fox, F.S.A., who made a special study of the subject, writes as follows:[4]
“By the last quarter of the third century the Romano-British fleet, on which no doubt dependence had been placed for the protection of the east and south coasts from raids by plundering bands of rovers from over the seas, had evidently failed to afford that protection. Whether it was that the fleet was not numerous enough, or for whatever reason, the Roman government determined to supplement its first line of defence by a second, and this was achieved by the erection of forts capable of holding from 500 to 1,000 men each, on points of the coast-line extending from the mouth of the Wash to Pevensey on the coast of Sussex. The coast-line indicated received the name of Litus Saxonicum, and the nine fortresses which guarded it are called ‘the forts of the Saxon Shore.’”
The following were the nine fortresses referred to with the modern place-names:
It will be observed that the various fortresses in this chain of defensive works occur at irregular distances on or near the coast-line, and on examination it will be found that in most cases good reason exists for the selection of the various sites.
1. Branodunum
There is sufficient evidence to identify the Roman fort of Branodunum with some ruins lying to the east of Brancaster, a village situated near the north-western corner of Norfolk, on the shores of the Wash. The only early mention of the place is found in the “Notitia Imperii,” a catalogue of the distribution of the imperial military, naval, and civilian officers throughout the Roman world. From this remarkable work, a compilation which has come down to us from a very early period, it appears that the “Comes Littoris Saxonici” (the Count of the Saxon Shore) had under him nine subordinate officers, called Praepositi, distributed round the coasts of Norfolk, Essex, Kent, Sussex, and Hampshire. The fortress at Brancaster is now in a very much ruined state, and but little can be gathered of its original form from a casual or superficial examination. Excavations and careful searches made about the middle of the nineteenth century brought to light many facts about its plan.[5] The fortress was a square of 190 yards and the angles were irregularly rounded. Exclusive of ashlar, the walls were found to be 10 feet thick, and bounded with large blocks of white sandstone. At one of the roughly rounded angles the ashlar facing remained intact. It consisted of blocks of sandstone firmly set in mortar with joints of three inches minimum thickness.
Traces were found within the walls of small apartments adjoining the main walls into which the smaller walls were regularly bonded, pointing to contemporaneity of the work.