However , the system of military reforms and the Burghal Hidage introduced by Edward the Elder enabled Alfred 's successors to retake control of the lands occupied in the North of England by the Danes .
It was under Alfred that the Viking threat was contained .
The system of military reforms and the Burghal Hidage introduced by Edward the Elder enabled Alfred 's successors to retake control of the lands occupied in the North of England by the Danes .
It was under Alfred that the Viking threat was contained .