In the reign of Stephen Yorkshire resumed its early eleventh-century position as a frontier county. The king was unable to prevent Scottish incursions into Cumbria, Northumberland and Durham in January 1136 and January 1138; and his retaliatory campaign of February 1138 did nothing to provide security against further attacks. The Scots were ceded the lordship of Carlisle in the first treaty of Durham in 1136, and the earldom of Northumbria in the second treaty of Durham in 1139. In Yorkshire Stephen placed royal administrative and military power in the hands of a single magnate, William earl of York; a policy which resembles the frontier strategy of previous English kings in the marcher counties on the border with Wales. It was a policy which failed to safeguard Yorkshire from a further extension of Scottish authority and influence.

This chapter will elucidate and explain the growth of Scottish power in the far north of England and Yorkshire in Stephen's reign, and King David's ultimate aims within the region. It will reveal that the scope of Scottish ambitions in England during the anarchy may have been much broader than has hitherto been realised.