Describe the border wars between England and Wales in the High Middle Ages. How did the English control the borders and eventually conquer the Welsh?

Although it was a poor country riddled with petty kingdoms, Wales was the one region in southern Britain that survived the Anglo-Saxon onslaught following William the Conqueror's victory on the island. The main stay of Wales survival came from its mountainous and wooded terrain, and the very fact that the many rivaling kingdoms within its own borders established a ready-made guerrilla warfare that the royalty of England was ill-prepared to subjugate. Because of the lack …

…established until a revolt in 1400. However, the English logistics and establishment of power within Wales was too great, and even with the loss of a few under-garrisoned fortresses during the revolt, complete subjugation of the region came in 1409, when French civil war decimated any additional aid to the Welsh and the English were quick to regain the castles that formed the ring--mainly Beaumaris, Aberystwyth, Harlech, and Conwy--and the independent nation of Wales was forever lost.