The Treaty of Wallingford, also known as the Treaty of Winchester or the Treaty of Westminster, was an agreement reached in England in the summer of 1153. It effectively ended a civil war known as the Anarchy (1135–54), caused by a dispute over the English crown between King Stephen and Empress Matilda. The Treaty of Wallingford allowed Stephen to keep the throne until his death (which was to come in October 1154), but ensured that he would be succeeded by Matilda's son Henry II.