But with the fall of the Danelaw the British princes were again brought to submission, and when in the midst of the Confessor's reign the Welsh seized on a quarrel between the houses of Leofric and Godwine to cross the border and carry their attacks into England itself, the victories of Harold reasserted the English supremacy.

Disembarking on the coast his light-armed troops he penetrated to the heart of the mountains, and the successors of the Welsh prince Gruffydd, whose head was the trophy of the campaign, swore to observe the old fealty and render the old tribute to the English Crown.
[Sidenote: Wales and the Normans] A far more desperate struggle began when the wave of Norman conquest broke on the Welsh frontier.

A chain of great earldoms, settled by William along the border-land, at once bridled the old marauding forays.

From his county palatine of Chester Hugh the Wolf harried Flintshire into a desert, Robert of Belesme in his earldom of Shrewsbury "slew the Welsh," says a chronicler, "like sheep, conquered them, enslaved them and flayed them with nails of iron." The earldom of Gloucester curbed Britain along the lower Severn.

Backed by these greater baronies a horde of lesser adventurers obtained the royal "licence to make conquest on the Welsh." Monmouth and Abergavenny were seized and guarded by Norman castellans; Bernard of Neufmarche won the lordship of Brecknock; Roger of Montgomery raised the town and fortress in Powysland which still preserves his name.