In 985, AEthelred, the Unready, as after ages called him, from his lack of _rede_ or counsel, quarrelled with AElfric, ealdormen of the Mercians, whom he drove over sea.

The breach between Mercia and Wessex was thus widened, and as the Danish attacks continued without interruption the redeless king soon found himself comparatively isolated in his own paternal dominions.
Northumbria, under its earl, Uhtred (one of the house of Bamborough), and the Five Burgs under their Danish leaders, acted almost independently of Wessex throughout the whole of AEthelred's reign.

In 991 Sigeric, archbishop of Canterbury, advised that the Danes should be bought off by a payment of ten thousand pounds, an enormous sum; but it was raised somehow and duly paid.

In 992, the command of a naval force, gathered from the merchant craft of the Thames, was entrusted to AElfric, who had been recalled; and the Mercian leader went over on the eve of an engagement at London to the side of the enemy.

Bamborough was stormed and captured with great booty, and the host sailed up Humber mouth.
There they stood in the midst of the old Danish kingdom, and found the leading men of Northumbria and Lindsey by no means unfriendly to their invasion.