On the death of AEthelflaed in 918 he came boldly to the front.
Annexing Mercia to Wessex, and thus gathering the whole strength of the kingdom into his single hand, he undertook the systematic reduction of the Danelaw.

South of the Middle-English and the Fens lay a tract watered by the Ouse and the Nen--originally the district of a tribe known as the South-English, and now, like the Five Boroughs of the north, grouped round the towns of Bedford, Huntingdon, and Northampton.

The reduction of these was followed by that of East-Anglia; the northmen of the Fens submitted with Stamford, the Southumbrians with Nottingham.

Eadward's Mercian troops had already seized Manchester; he himself was preparing to complete his conquests, when in 924 the whole of the North suddenly laid itself at his feet.

Not merely Northumbria but the Scots and the Britons of Strathclyde "chose him to father and lord." [Sidenote: AEthelstan] The triumph was his last.