Chronica Majora. After 13 Jan 1237. In this year [his father] Llewellyn, prince of Wales (age 65), by special messengers sent word to the king that, as his time of life required that he should thenceforth abandon all strife and the tumult of war, and should for the future enjoy tranquillity and peace, he had determined to place himself and all his possessions under the authority and protection of him, the English king, and would hold his lands from him in all faith and friendship, and enter into an indissoluble treaty; and if the king should be proceeding on any expedition, he would to the best of his power, as his liege subject, promote it, by assisting him with troops, arms, horses, and money. To confirm and ratify this treaty, the bishops of Hereford and Chester [Note. In 1237 Chester wasn't a Bishopric?] were sent as mediators to bring the aforesaid matter to a conclusion. The cause of this message is said to have been that the said Llewellyn, owing to an attack of paralysis, was unable of himself to oppose the grievous attacks of his son Griffin (age 39), who was making war against him. Many of the nobles of Wales agreed to this treaty, and confirmed it at the same time as Llewellyn; some of them, however, strongly opposed their compacts. The faith of the Welsh is a want of faith, and they show no mercy when they have it in their power; and when fortune befriends them, they persecute those who fall into their power; but when defeated, they either fly or humble themselves: and such persons are never to be trusted, as the poet says, "I fear the Greeks, even when they bring gifts;" the philosopher Seneca also says, "You will never make safe treaty with any enemy."

In 1239 Gruffydd ap Llewellyn Aberffraw (age 41) was imprisoned at Criccieth Castle [Map].

In 1241 Gruffydd ap Llewellyn Aberffraw (age 43) was imprisoned at Tower of London [Map].

In 1248 Gruffydd ap Llewellyn Aberffraw was buried at Aberconwy Abbey [Map].

Chronica Majora. During all this time Griffin, the son of [his father] Llewellyn, had been detained in prison by his brother [his brother] David, who had treacherously summoned him to a friendly council. Griffin had gone there under the conduct of Richard, bishop of Bangor, and some other Welsh nobles; on account of which crime the said bishop left Wales, after excommunicating the said David. He now went to the [his uncle] king of England, and laid a severe complaint before him of this base crime, and earnestly entreated of the king to release Griffin, who was thus unjustly detained a prisoner by his nephew David, to prevent the taint of such an iniquitous transaction from reaching distant countries and the court of Rome, to the prejudice of his royal honour. The king, therefore, severely reproached his nephew David for his treachery, and both advised and ordered him to liberate his brother, and thus obtain a restoration of his good name, and absolution from the sentence of excommunication. This, however, David, obstinately refused to do, and told the king for certain, that if he were to release Griffin, Wales would never after enjoy security and peace. Griffin, being informed of this, secretly sent word to the king, that if he would release him from prison, he would in future hold his territory from him, the king; that he would faithfully pay him two hundred marks annually for it, with many thanks for his kind services; and he bound himself by oath to fulfil the same, and giving him at the same time a special hostage; besides this, that he would diligently assist him to subdue the Welsh at a distance, who were rebelling against him and were still unsubdued. Another most powerful Welsh chief, named Griffin, the son of Madoch, also promised the king trusty and unwearied assistance, if he would invade Wales, and make war against David, who was a false man, and acted unjustly to many of them.