It is not possible to credit David with any real affection for the cause of the empress or with any higher motive than selfish greed, and it can scarcely be claimed that he kept faith with Stephen. Such, however, were the difficulties of the English king, that, in spite of his crushing defeat, David reaped the advantages of victory. Peace was made in April, 1139, by the Treaty of Durham, which secured to Prince Henry the earldom of Northumberland, as an English fief. The Scottish border line, which had successively enclosed Strathclyde and part of Cumberland, and the Lothians, now extended to the Tees. David gave Stephen some assistance in 1139, but on the victory of the Empress Maud[37] at Lincoln, in 1141, David deserted the captive king, and was present, on the empress's side, at her defeat at Winchester, in 1141. Eight years later he entered into an agreement with the claimant, Henry Fitz-Empress, afterwards Henry II, by which the eldest son of the Scottish king was to retain his English fiefs, and David was to aid Henry against Stephen. An unsuccessful attempt on England followed--the last of David's numerous invasions. When he died, in 1153, he left Scotland in a position of power with regard to England such as she was never again to occupy. The religious devotion which secured for him a popular canonization (he was never actually canonized) can scarcely justify his conduct to Stephen. But it must be recollected that, throughout his reign, there is comparatively little racial antagonism between the two countries. David interfered in an English civil war, and took part, now on one side, and now on the other. But the whole effect of his life was to bring the nations more closely together through the Norman influences which he encouraged in Scotland. His son and heir held great fiefs in England,[38] and he granted tracts of land to Anglo-Norman nobles. A Bruce and a Balliol, who each held possessions both in Scotland and in England, tried to prevent the battle of the Standard. Their well-meant efforts proved fruitless; but the fact is notable and significant.