The Angevin Empire was a collection of territories in the late 12th and early 13th centuries, primarily ruled by the Plantagenet dynasty. It included regions such as England, Wales, Ireland, and large parts of France, notably Normandy and Aquitaine. The empire was established under the reign of Henry II and expanded through his marriage to Eleanor of Aquitaine. At its height, the Angevin Empire was one of the most powerful political entities in medieval Europe. It was characterized by a complex system of feudal relationships and conflicts, particularly with the French crown. The empire began to fragment after the death of King John, leading to the loss of many territories in France.