Great Heathen Army
Northumbria, East Anglia, MercAn enlarged army arrived that the Anglo-Saxons described as the Great Heathen Army. This was reinforced in 871 by the Great Summer Army. Within ten years nearly all of the Anglo-Saxon kingdoms fell to the invaders: Northumbria in 867, East Anglia in 869, and nearly all of Mercia in 874–77. Kingdoms, centres of learning, archives, and churches all fell before the onslaught from the invading Danes. Only the Kingdom of Wessex was able to survive.