By 1153, the castle garrison was running very low on food, and Roger made a deal with Stephen allowing him to leave the castle with his followers. Henry, the Empress' son and the future Henry II, then intervened, marching his forces to relieve the castle and placing Stephen's counter-castles under siege himself. King Stephen marched back from Oxford, and the two forces confronted each other on the meadows outside the castle. The result was an embryonic peace deal called the Treaty of Wallingford, leading on to the permanent Treaty of Winchester that would ultimately bring an end to the civil war and install Henry as king following Stephen's death in 1153. Brien, who had no children, chose to enter a monastery, and surrendered Wallingford Castle to Henry at the end of the conflict in 1153.