Ancient Britain and the Invasions of Julius Caesar

by T. Rice Holmes

It remains only to consider the objections which have been made to the identification of the Portus Itius with Boulogne.

1. The very fact that Boulogne was called Gesoriacum is regarded by Long[2898] as presumptive evidence that it was not called Portus Itius.

Desjardins,[2899] who evidently regards this as a serious objection, has taken great pains to remove it. He argues that the Portus Itius was not exactly the same as the imperial harbour of Gesoriacum, but that it comprised that part of the estuary of the Liane which lies between Bréquerecque and Isques; and, he triumphantly remarks, the name ‘Isques’ is derived from Itius. But ‘Isques’ cannot have been derived from Itius: the names ‘Ausques’,‘Quesques’, ‘Clerques’, ‘Setques’, and ‘Wisques’ are derived from Alciacum, Kessiacum, Quertliacum, Sethiacum, and Wiciacum; and the inference is that not Itius but Isiacum would have been transformed into ‘Isques’.[2900] Rudolf Schneider,[2901] who is too honest and too hard-headed to be deluded by Desjardins’s attempt to draw a distinction between Gesoriacum and Portus Itius, frankly admits that the unrecorded change of name has not been explained. But is there anything to explain? ‘Portus Itius’ is not, properly speaking, a name at all: it does not designate a town; it means simply ‘the Itian harbour’. Long saw nothing inexplicable in the fact that Gesoriacum was called by Pliny portus [Morinorum] Britannicus: why, then, should he have found it impossible to believe that its harbour was called by Caesar portus Itius?[2902] Was not the port of Athens called the Piraeus?

2. Long, after making the amazing remark that ‘such a port as Boulogne would have been quite useless in Caesar’s second expedition’, says that ‘the Romans estimated the distance from Boulogne to the British coast at fifty Roman miles; but this is too much.... However, they were right in making the distance more than the distance from Itius to the nearest point of the British coast; and the conclusion is that Gesoriacum and Itius were different places.’[2903]

The conclusion is simply that, assuming the identity of Gesoriacum with the Portus Itius, Caesar’s estimate of the distance from Gesoriacum to Britain was different from that of later writers. Besides, the only one of ‘the Romans’, as far as we know, who ‘estimated the distance from Boulogne to the British coast at fifty Roman miles’ was Pliny;[2904] and it may be presumed that by ‘the British coast’ he meant Rutupiae, or Richborough, which was a port, if not the chief port, of arrival in his day. For he estimated the shortest passage at fifty Roman miles: according to Dion Cassius,[2905] the shortest passage was 450 stades; and this, according to the Itinerary of Antonine,[2906] was precisely the length of the passage from Boulogne to Richborough.

Long goes on to say that in the Itinerary of Antonine the distance from Boulogne to Richborough ‘was estimated at 450 stadia; and, if we follow d’Anville in estimating this maritime stadium at ten to the Roman mile, the distance is fairly given. So if we take the 320 stadia which Strabo gives as the length of Caesar’s voyages, we have thirty-two Roman miles; or, if we take the reading which Eustathius, copying Strabo, has in his commentary on Dionysius, 300 stadia, we have exactly thirty Roman miles, as in Caesar’s text. The conclusion is that, in addition to the fact of Boulogne (Gesoriacum) and Ouissant (Itius) having different names, the ancient authorities place them at different distances from the British coast.’[2907]

Again Long’s conclusion is at fault. To begin with, Strabo did not estimate the maritime stadium at ten, but at eight to the Roman mile.[2908] Assuming, however, that he did estimate it at one-tenth of a Roman mile, there is no reason to suppose that when Caesar estimated the distance from the Portus Itius to Britain, he meant the distance to Richborough; and the only conclusion that can be drawn from Long’s data is that ‘the ancient authorities’ reckoned the length of Caesar’s voyage less than the distance between Richborough and Boulogne. And when Long says that the estimated distance, 450 stadia, from Boulogne to Richborough ‘is fairly given’, it is amusing to find him admitting that Caesar’s estimate of 30 miles ‘exceeds the distance from Wissant to the nearest part of the English coast, and it is about the true distance from Boulogne to the same part of the English coast’. Thus, on Long’s own showing, Caesar’s estimate of the distance from the Portus Itius to the British coast corresponds with the actual distance from Boulogne to the same, and the estimate of the Itinerary is equally true. The reader who has followed him so far will hardly be surprised by his remark, that ‘even a real good harbour would have been useless to Caesar’.[2909]

3. Heller,[2910] after quoting the statement of Pliny as to the length of the shortest passage from Boulogne to Britain, and the statement of the Itinerary of Antonine as to the distance from Boulogne to Richborough, argues (a) that, as they overestimated the distance from Gaul to Britain, Caesar probably did the same; (b) that if Pliny had identified Boulogne with the Portus Itius, he would not have estimated the distance of Boulogne from the nearest point of Britain at 50 miles, but would have followed Caesar and written ‘about 30’; (c) that if Caesar had started from Boulogne, he would, according to the usual tendency of the ancients, have overestimated the distance from Boulogne to Britain, and would therefore have reckoned it at considerably more than ‘about 30 miles’, seeing that the actual distance from Boulogne to Dover is 33.

The first of these arguments, if it had come from a tiro, might have been passed over with a smile; but one would hardly have expected it from Heller. The third is based upon a misleading statement;[2911] and even if we could be sure that Caesar overestimated the length of his voyage, it would be inconclusive, for, as we have seen,[2912] it is not improbable that he estimated it at 40 Roman miles. And as for Pliny, ‘the shortest passage,’ which he estimated at 50 miles, was probably, I repeat, the passage from Boulogne to Richborough.

4. H. L. Long,[2913] if I do not misunderstand him, argues that there could have been no port at Ambleteuse in the days of Caesar. Speaking of ‘the immense irruption of blown sand’, he maintains that ‘this dune ... acts as a dam to the drainage of the valley; an interruption which must have produced swamps in former days, and is now but imperfectly corrected by an artificial channel, the embouchure of which forms the little harbour of Ambleteuse’.