The conquest of England by duke William of Normandy in 1066 changed things, not just for the English but also for their Celtic neighbours. England in 1066 was probably the most centralised kingdom in Europe, with power and landownership concentrated in very few hands. The three great battles of that year thinned the ranks of the English royal family and nobility, making the subsequent task of the Normans of consolidating their conquest much easier. There were fierce peasant rebellions but they were uncoordinated and lacked credible leadership. By 1070 it was all over and England’s new French-speaking ruling class was secure in its possession of the country. The Normans practised strict primogeniture. Younger sons of the nobility would be given a good training in war and then left to shift for themselves. This surplus of landless warriors made the Normans natural colonists, in Italy and the Holy Land, as well as Britain. William the Conqueror was always more interested in Normandy than Wales, but he was happy enough to allow Hugh the Fat, Roger of Montgomery and William Fitzosbern, of the marcher earldoms of Chester, Shrewsbury and Hereford, to enlarge their lordships at the expense of the Welsh.
At first the Normans made rapid progress into Wales. The small kingdoms of Brycheiniog (Brecon), Gwent and Morgannwg (Glamorgan) had all been conquered by 1093, and by 1114, when Henry I launched a massive three-pronged invasion of Wales, the Normans had overrun most of Deheubarth, penetrated Powys along the valleys of the Dee and Severn and occupied the coastal areas of Gwynedd from the mouth of the Dee as far as Anglesey. Something like 500 earth and timber motte and bailey castles were built to consolidate these conquests, and more than a dozen new marcher lordships were created (‘march’ is cognate with German ‘mark’ and means ‘border’). A complete Norman conquest seemed only a few years away, yet their reach had far exceeded their grasp. Civil war in England during the reign of King Stephen (1135-54) deprived the marcher lords of royal support and the Welsh recovered around half the territory they had lost. The areas where the marcher lords held on most securely - the fertile farmlands of Gwent, the Vale of Glamorgan, the Gower and south Pembrokeshire - were those which had been suitable for the transplantation of the English manorial system and were attractive to English, and also Flemish, peasant colonists.
Stephen’s successor Henry II (r. 1154-89), one of medieval England’s most able rulers, launched several campaigns to try to restore the English position in Wales. They all failed. Henry’s sons, Richard and John, and his grandson Henry HI would all fare no better in their campaigns against the Welsh. The churchman Gerald of Wales (1146-1223), a prolific writer on Wales and Ireland, accurately identified the reasons for the failure of English campaigns. One of the reasons, he thought, was a moral one. ‘The English are striving for power, the Welsh for freedom; the English are fighting for material gain, the Welsh to avoid a disaster; the English soldiers are hired mercenaries, the Welsh are defending their homeland.’ Because the Welsh were more lightly armed and armoured than the English, they could not fight them on equal terms. Therefore, the Welsh avoided open battle and employed harassing tactics, making the best use of rugged terrain, where the less mobile English were at a disadvantage. It was impossible, Gerald thought, ‘to conquer in one battle a people which will never draw up its forces to engage an enemy army in the field, and will never allow itself to be besieged inside fortified strong points’. Gerald, too, was keenly aware of the financial costs. Campaigns in Wales were expensive and little in the way of plunder could be expected to defray the costs. Henry IPs campaign of 1165, for example, cost ?7,500 at a time when his income from the crown lands was less than ?10,000 a year. This was an enormous amount of money down the drain with nothing at all to show for it. There was also the problem that the post-Conquest kings of England were frequently distracted by the need to defend their French lands from the king of France. If only the Welsh would unite under one leader, mused Gerald, the English would never conquer them.
The dominating figure of later twelfth-century Wales was Rhys ap Gruffydd (r. 1155-97), king of Deheubarth, also known as the Lord Rhys, who conquered several of the marcher lordships in mid and south Wales. A ‘moderniser’ who built stone castles and championed church and monastic reform, Rhys was also a notable patron of Welsh culture and held the first recorded eisteddfod in 1176. Succession disputes broke up Deheubarth after Rhys’s death but it was Gwynedd, not England, that was the main beneficiary of this. England was paralysed by a civil war that broke out at the end ofjohn’s reign (1199-1216), and the king of Gwynedd, Llywelyn ab lorwerth (r. 1195-1240) was able to conquer the other Welsh kingdoms without English interference. For this feat he earned the title Llywelyn the Great. Llywelyn tried to ensure that his kingdom remained intact after his death by breaking with custom and appointing his son Dafydd (d. 1246) as his sole heir. Unfortunately, Dafydd proved to be an inept ruler and his kingdom collapsed as a result of rebellions and English intervention. Welsh unity was restored by Dafydd’s nephew Llywelyn ap Gruffydd (r. 1246-82), who adopted the title ‘Prince of Wales’ in 1258.
Devastating attacks on the marcher lordships forced Henry III of England to recognise Llywelyn’s title and his overlordship of Wales by the Treaty of Montgomery in 1267. This was a step on the way towards the creation of a national kingship that a stronger English king would surely have refused, but at least Henry forced Llywelyn to acknowledge that he held his title as a vassal of the English crown.