one inevitable division between north and south. Another is provided by 
underlying geological features which have placed a large tract of high, barren 
moor land and hilly country - commonly though incorrectly called 'the Cheviots' - 
between the Solway Firth and a point only fifteen miles up the River Tweed from 
the North Sea4. Even although those historians who have seen this as some kind of 
political 'no man's land' are in error - for the line of the Border was always pretty 
clearly understood in medieval times, and even demarcated in places - nevertheless 
the tract of inhospitable wilderness formed a geographical 'no man's land' which 
must often have discouraged one side or the other from sustained aggression. The 
existence of the Cheviot barrier, averaging around 400 m. above sea level, meant 
that English aggressors would find it necessary to push as far north as the Firth of 
Forth to fix a secure and worthwhile frontier, while Scottish aggressors, 
correspondingly, would wish to incorporate the northern English river systems of 
Eden and Tyne. For much of the medieval period it was beyond the resources of 
either the English or Scottish kings to hold such extended frontiers for more than a 
few years together. There were thus powerful considerations working in favour of 
the Solway-Esk-Cheviot-Tweed alignment in the formative period when the 
medieval kingdoms of England and Scotland were taking shape. It was of decisive 
significance for the location and structure of the Borders that these historic 
kingdoms grew out of, respectively, a southern (i.e. West Saxon) and a northern 
(i.e. Scoto-Pictish) kingdom. Only thus can we understand how a region which 
otherwise possessed a high degree of unity - Northumbria on the eastern side and 
Cumbria on the western side - came to be divided across the middle5. The unity of 
at least the northern half of Northumbria (what had been the ancient kingdom of 
Bemicia) was still recognized well into the thirteenth century before the king of 
Scots, by the Treaty of York of 1237, was persuaded to abandon finally his 
ancestral claims to the four northernmost counties of England6. Of these, the two 
lying east of the Pennine watershed, Northumberland and Durham, formed 
essential components of Bemicia. The western pair, Cumberland and 
Westmorland, were equally integral parts of the ancient kingdom of Cumbria or 
Strathclyde. Even after Scottish royal claims upon them were abandoned in 1237 
the bishops of Glasgow could still declare publicly and formally that the southern 
limit of their diocese was marked by the Rey or Rere Cross on Stainmore 
Common, the boundary dividing Westmorland from Yorkshire, thus effectively 
4 Geological Map of the United Kingdom, North (Institute of Geological Sciences, 3rd edition solid, 1979). 
5 Blair, P. Hunter, "The Bemicians and their northern frontier", in: Studies in Early British History, ed. 
Chadwick, N. (Cambridge, 1954); Kirby, D.P., "Strathclyde and Cumbria: a survey of historical 
development to 1092", in: Transactions of the Cumberland and Westmorland Antiquarian and 
Archaeological Society, New Series, 62 (1962). For the general background, see Barrow, G.W.S., The 
Kingdom of the Scots (1973), 139-61 and Barrow, G.W.S., "Frontier and Settlement: which influenced 
which? England and Scotland^ 100-1300", in: Medieval Frontier Societies, ed. Bartlett, R. and 
Mackay, A. (Oxford, 1989), 2-21. 
6 Stones, E.L.G., Anglo-Scottish Relations, 1174-1328. Some Selected Documents (Oxford, 1970), 38- 
53. 
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