The area of this study, the English upands and the Northumbrian coastal plain, has a border society with its own peculiarities, so ably studied recently by Philip Dixon,’ an area where, in the fifteenth and sixteenth centuries ‘men have doubted whether thieves or true men do most abound. The area in the later medieval period stands apart from the rest of Qle country, perhaps more so than the Welsh Marches. But for earlier periods, when it was just as sparsely populated, the area should be examined to understand the events of the twelfth century.
Professor Barrow has shown in his 1966 study of the Anglo-Scottish border, how before the treaty of York in 1237 there was never ‘a sizeable tract of territory (as distinct from small pieces of no man's or debatable land) where the English and Scottish kingdoms as it were shaded off into each other': the line of the border on the west was determined by Solway and Esk, and on the east by the river Tweed. Before the decline of Northumbria, however, the region between the rivers Tyne and Forth fonned a culttiral, and frequentIy, a political unity. In the seventh and eighth centuries the natural border zone, where the rivers Carron and Avon entered the Forth, formed the frontier with the Celtic world. This is well demonstated by the location of such Anglian monasteries as Tynningehanl and Coldingham, and particularly by the earliest estates of Lindisfarne. Barrow has shown how the border could have meant very little, when in 655, Lindisfarne was given twelve estates by King Oswy. The estates along the upper Bowmont Water included two now in England (Mindrum and Shotton) and seven now in Scotland (Sourhope, Halterburn, Ciifton, Shereburgh, Staerough and Yetholm).
The main impetus of Scandinavian invasion, combined with the failing of Northumbria, occurred at the time when the Scoto-Pictish kingdom, north of the river Forth, managed to maintain its independence and integrity despite Norwegian and Danish onslaughts. Once Scandinavian invasion and settlement diminished, it was clear that sooner or later Saxon expansion northwards would coincide with the movement of Scots southwards. The river Tweed seems now to assume importance: this is well demonstrated in the History of saint Cutlhbert, in which Lindisfarnensis terra is said to extend ‘from Tweed to Warenmouth'.