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 invasion of Ireland had the backing of King Henry II of England and was authorized by Pope Adrian IV. In the summer of 1170, there were two further Norman landings, led by Richard "Strongbow" de Clare. By May 1171, Strongbow had assumed control of Leinster and seized the Norse-Irish city kingdoms of Dublin, Waterford, and Wexford. That summer, High King Ruaidrí Ua Conchobair (Rory O'Connor) led an Irish counteroffensive against the Normans, who nevertheless managed to hold most of their conquered territory. In October 1171, King Henry landed with a large army in Ireland to establish control over both the Anglo-Normans and the