The Great Heathen Army, also known as the Viking Great Army, was a coalition of Scandinavian warriors who invaded England in AD 865. Since the late 8th century, the Vikings had been engaging in raids on centres of wealth, such as monasteries. The Great Heathen Army was much larger and aimed to conquer and occupy the four kingdoms of East Anglia, Northumbria, Mercia and Wessex.

The Kingdom of the East Angles, informally known as the Kingdom of East Anglia, was a small independent kingdom of the Angles during the Anglo-Saxon period comprising what are now the English counties of Norfolk and Suffolk and perhaps the eastern part of the Fens, the area still known as East Anglia.