Identification: the river Adur or the river Ouse (East Sussex)
Richmond and Crawford indicate that all three of the Vatican, Basle and Paris manuscripts of the Ravenna Cosmography give the form Raxtomessasenna, but nonetheless they split the name up into Raxtomessa and Senua, treating these as two different river-names. But it is likely that the manuscripts do in fact give the correct form. Raxtomessa is a land-name and senna was probably originally serna, this being a river-suffix in the river-letters s and r corresponding to the hill-letters r and m in Raxtomessa. The full name means ‘Raxtomessa river’. The name Raxtomessa refers to a location on raised ground, bounded by a steep slope and overlooking a river (for an explanation of the essa-ending see Chapter 4: place-names with an essa-type ending). The river-letters corresponding to the hill-letters r, s and m of Raxtomessa (the x stands in for cs) are s, b and r. It would appear that the b was at some stage dropped altogether, leaving the river-letters s and r. Apparently the river Adur was previously called the Sore, so it is clearly possible that the Raxtomessasenna was the Adur. The Celtic fort or settlement called Raxtomessa may have been at Old Shoreham, if there is a steep slope down to the river there, or further upriver, where there is no shortage of steep slopes as far as Steyning/Upper Beeding.
But note another possibility. If the river-name Ouse, a river a little east of the Adur, is a genuine old name and not a relatively modern creation, then the name could be derived from the river-suffix serna, just as the Yorkshire Ouse is believed to be derived from the Celtic river-name Isur. In this case the Raxtomessaserna could have been the East Sussex Ouse and the Celtic settlement called Raxtomessa, at the top of a high, steep hill and overlooking the river, could have been in the Newhaven area, where there are high, steep hills on both sides of the river, or a little further north at or close to Lewes, where there are also high, steep hills close to the river. The most likely candidate would be the Iron Age hill-fort on Mount Caburn, which does indeed stand at the top of a high, steep slope and overlooks the river Ouse.
[NB. Detailed information as to the different river-letters and as to how they were combined to form compound river-names, together with information as to the four categories of Celtic river-names, is given in Chapter 19: the rivers of Roman Britain. Detailed information as to the different hill-letters is given in Chapter 1 and information as to how the hill-letters were combined to form compound place-names is given in Chapter 2]
[Navigating tip: simply close this window to return to Chapter 19, if that is where you came from. Click on Prev below to proceed to the notes for Trisantonis. Click on Next below to go back to the notes for Novia. Click here on Romano-British place-names to go to the Contents page.]