Eadwig was King of England from 23 November 955 until his death in 959. He was the elder son of Edmund I and his first wife Ælfgifu, who died in 944. Eadwig and his brother Edgar were young children when their father was killed trying to rescue his seneschal from attack by an outlawed thief on 26 May 946. As Edmund's sons were too young to rule he was succeeded by his brother Eadred, who suffered from ill health and died unmarried in his early 30s.

Eadwig became king in 955 aged about fifteen and was no more than twenty when he died in 959. He clashed at the beginning of his reign with Dunstan, the powerful Abbot of Glastonbury and future Archbishop of Canterbury, and exiled him to Flanders. He later came to be seen as an enemy of monasteries, but most historians think that this reputation is unfair. In 956, he issued more than sixty charters transferring land, a yearly total unmatched by any other European king before the twelfth century, and this is seen by some historians as either an attempt to buy support or rewarding his favourites at the expense of the powerful old guard of the previous reign.

In 957, the kingdom was divided between Eadwig, who kept the territory south of the Thames, and Edgar, who became king of the land north of it. Historians disagree whether this had been planned since the beginning of his reign or was the result of a successful revolt brought about by Eadwig's enemies. The following year, Oda, Archbishop of Canterbury, separated Eadwig from his wife Ælfgifu on the ground that they were too closely related. Edgar succeeded to the whole kingdom when Eadwig died in 959.

The Benedictine reform movement became dominant in Edgar's reign with his strong support, and monastic writers praised him and condemned Eadwig as irresponsible and incompetent. Their view was generally accepted by historians until the late twentieth century, but in the twenty-first century some historians have defended Eadwig, while others see his character and the events of his reign as unclear due to uncertain and conflicting evidence.