The north of England had been under Danish control for much of the previous half-century. William the Conqueror led a campaign in the winter of 1069-70 to subjugate the local population, known as the Harrying of the North. Whole villages were burnt and one estimate has put the death toll at 100,000. Food stores were deliberately destroyed so that even those who survived the initial slaughter would face starvation over the winter months. This campaign allowed William to replace the local Anglo-Danish lords with Norman ones of his own choice, who would be loyal to the crown. However, the rest of the population largely retained a Viking character for at least another century.
Editors. "Harrying of the North". The Literary Encyclopedia. First published 31 July 2012
[http://www.litencyc.com/php/stopics.php?rec=true&UID=1948, accessed 02 May 2016.]