Stephen, King of England recognised Stephen's son Eustace as Duke of Normandy in exchange for Eustace giving fealty to the French king. Stephen was less successful, however, in regaining the Argentan province along the Normandy and Anjou border, which Geoffrey had taken at the end of 1135. Stephen formed an army to retake it, but the frictions between his Flemish mercenary forces led by William of Ypres and the local Norman barons resulted in a battle between the two halves of his army. The Norman forces then deserted the King, forcing Stephen to give up his campaign. Stephen agreed to another truce with Geoffrey,
Norman conquest of England had moored for the winter south of the Humber in Lincolnshire, and drove them back to the north bank. Leaving Robert of Mortain in charge of Lincolnshire, he turned west and defeated the Mercian rebels in battle at Stafford. When the Danes attempted to return to Lincolnshire, the Norman forces there again drove them back across the Humber. William advanced into Northumbria, defeating an attempt to block his crossing of the swollen River Aire at Pontefract. The Danes fled at his approach, and he occupied York. He bought off the Danes, who agreed to leave England in the spring, and