The Danish king Svein raided England in 994, unsuccessfully attempting to besiege London.

He returned in 1003 after the St Brice's Day massacre in 1002, when Æthelred, king of England, had many Danes living outside the Danelaw killed.

The Viking presence in England continued and in 1013 Svein, accompanied by his younger son Cnut, was accepted as king.

[2] During this time Eadric Streona, the ealdorman of Mercia, is recorded in the Anglo-Saxon Chronicle as having hindered the efforts of the English to resist the Danish invaders.

[3] Cnut, possibly now claiming the title king of Denmark, appeared at Sandwich in September 1015 and ravaged Dorset, Wiltshire and Somerset.

[2] Edmund had raised an army late in 1015 but withdrew after learning Eadric intended to betray him to the invaders.

[5] Edmund was then joined by his brother in law, Earl Uhtred of Northumbria, and attacked towns which according to Anglo-Norman chronicler William of Malmesbury, had sided with Cnut.

While the Danes were besieging London, they learned of the army being levied in Wessex and quickly marched south.