On the death of the Lord Rees, one of the grandsons of Owen Gwynedd becomes the central figure in Welsh history. Llywelyn the Great rose into power in 1194, and reigned until 1240 - a long reign, and in many ways the most important of all the reigns of the Welsh princes.

Llywelyn's first task was to become sole ruler in Gwynedd. The sons of Owen Gwynedd had divided the strong Gwynedd left them by their father, and their nobles and priests could not decide which of the sons was to be supreme. Iorwerth, the poet Howel, David, Maelgwn, Rhodri, tried to get Gwynedd, or portions of it. Eventually, David I. became king; but soon a strong opposition placed Llywelyn, the able son of Iorwerth, on the throne. Uncles and cousins showed some jealousy; but the growing power of Llywelyn soon made them obey him with gradually diminishing envy.

His next task was to attach the other princes of Wales to him, now that the Lord Rees and Owen Cyveiliog were dead. To begin with, he had to deal with the astute Gwenwynwyn, the son of Owen Cyveiliog; and he had to be forced to submit. He then turned to the many sons and grandsons of the Lord Rees - Maelgwn and Rees the Hoarse especially. They called John, King of England, into Wales; but they soon found that Llywelyn was a better master than John and his barons. Gradually Llywelyn established a council of chiefs - partly a board of conciliation, and partly an executive body. It was nothing new; but it was a striking picture of the way in which Llywelyn meant to join the princes into one organised political body.

His third task was to begin to unite Norman barons and Welsh chiefs under his own rule. He had to begin in the old way, by using force; and Ranulph of Chester and the Clares trembled for the safety of their castles. He then offered political alliance; and some of the Norman families of the greatest importance in the reign of John - the Earl of Chester, the family of Braose, and the Marshalls of Pembroke- -became his allies. His other step was to unite Welsh and Norman families by marriage. He himself married a daughter of King John, and he gave his own daughters in marriage to a Braose and a Mortimer. It is through the dark-haired Gladys, who married Ralph Mortimer, that the kings of England can trace their descent from the House of Cunedda.

Llywelyn's last great task was to make relations between England and Wales relations of peace and amity. During his long reign, he saw three kings on the throne of England - the crusader Richard, the able John, and the worthless and mean Henry III. It was with John that he had most to do, the king whose originality and vices have puzzled and shocked so many historians. John helped him to crush Gwenwynwyn, then helped the jealous Welsh princes to check the growth of his power. Llywelyn saw that it was his policy, as long as John was alive, to join the English barons. They were then trying to force Magna Carta upon the King, that great document which prevented John from interfering with the privileges of his barons. In that document John promises, in three clauses, that he will observe the rights of Welshmen and the law of Wales.

When John died in 1216, and his young son Henry succeeded him, the policy of England was guided by William Marshall Earl of Pembroke. William Marshall was one of the ministers of Henry II., and by his marriage with the daughter of Strongbow, the conqueror of Ireland, he had become Earl of Pembroke. It was with him that Llywelyn had now to deal. He was too strong in Pembroke to be attacked, but his very presence made it easier for Llywelyn to retain the allegiance of the chiefs who would have been in danger from the Norman barons if Llywelyn's protection were taken away. In 1219 the great William Marshall died; and changes in English politics forced his sons into an alliance with Llywelyn.

Llywelyn's title of Great is given him by his Norman and English contemporaries. He was great as a general; his detection of trouble before the storm broke, his instant determination and rapidity of movements, his ever-ready munitions for battle and siege, made his later campaigns always successful. He felt that he was carrying on war in his own country; so his wars were not wars of devastation, but the crushing of armies and the razing of castles.

He took an interest in the three great agents in the civilisation of the time - the bard, the monk, and the friar. The bard was as welcome as ever at his court; the monk, welcomed by Owen Gwynedd before, was given another home at Aber Conway. Llywelyn extended his welcome to the friar, and he was given a home at Llan Vaes in Anglesey, on the shores of the Menai. The friar brought a higher ideal than that of the monk; his aim was salvation, not by prayer in the solitude of a mountain glen, but by service where men were thickest together - even in streets made foul by vice, and haunted by leprosy. Of the Mendicant Orders, the Franciscans were the best known in Wales; and, of all Orders of that day, it was they who sympathised most deeply with the sorrows of men. And it was this which, a little later on, brought them so much into politics.

Great and successful in war and policy, in touch with the noblest influences in the life of the time, Llywelyn applied himself to one last task. His companions and allies had nearly all died before him; but he wished that the peace and unity, which they had established, should live after them. He had two sons - Griffith, who was the champion of independence; and David, who wished for peace with England. Llywelyn laid more stress on strong government at home than on the repudiation of feudal allegiance to the King of England. So he persuaded the council of princes at Strata Florida to accept David as his successor.