abstained from attacking England since 1039, and had been rewarded for his fidelity by the grant of all the English land which lay to the west of the Dee (Domesday, p. 263 ; cf. Norm. Conq. ii. 399), now seems to have joined his forces with Swegen, son of Godwine, the earl of the southern border lands, in an expedition against the sons of Rhydderch (A.-S. Chron. sub an. 1046; cf. Ann. Cambr. sub an.) But in 1047 the nobles of Ystrad Towy and Dyved rose against their northern master and treacherously cut off 140 men of his household. In revenge Gruffydd laid waste all Ystrad Towy and Dyved. Two years later occurred a cruel ravaging of Deheubarth by the Irish allies of Gruffydd ab Rhydderch (Brut y Tywys. sub an. 1049; A.-S. Chron.; Flor. Wig.) At last in 1055 Gruffydd slew his southern namesake, and thus became 'king of the Britons' and master of north and south alike.
In 1052 Gruffydd ravaged Herefordshire 'until he came nigh unto Leominster,' and 'on the same day on which thirteen years before Eadwine had been slain he slew many of the English as well as Frenchmen of the castle.' Soon after the death of the southern Gruffydd chance gave him an opportunity of inflicting a severe blow on the English. Ælfgar, son of Leofric, and brother of the Eadwine slain by Gruffydd in 1039, was now outlawed, and, having collected eighteen ships of northmen from Ireland, requested Gruffydd's co-operation in his war against King Edward and Harold. Gruffydd raised a great army from every part of Wales, and in combination with Ælfgar ravaged Archenfield, a district of Herefordshire, with a severity that was remembered so long afterwards as the time of the Domesday inquest. On 24 Oct., two miles from Hereford, the timid French Earl Ralph, King Edward's nephew, was driven into a disgraceful retreat before the motley army of the allies. The town was burnt, the minster plundered, and the castle razed. Gruffydd returned with a great booty (Brut y Tywys. sub an. 1054). Harold, son of Godwine, was now sent out to revenge the capture of Hereford, and Gruffydd did not venture on a pitched battle. He retreated into South Wales, and Harold did not venture beyond the district of Straddele in Herefordshire. Negotiations were now begun, and Gruffydd and Ælfgar met Harold at Billingsley in Shropshire, where peace was made and Ælfgar restored. As the result of Gruffydd's rebellion he lost the lands beyond the Dee, which Edward had previously given him.
Gruffydd had no intention of keeping peace, and now allied himself with a northman strangely described as 'Magnus, son of Harold king of Germany,' possibly a son of Harold Hardrada (Freeman, Norm. Conq. ii. 396). In the spring of 1056 the borders were again ravaged. Again the storm burst round Hereford, which Harold had restored, and where his chaplain, Leofgar, its newly made bishop, headed the resistance. But on 17 June Gruffydd won another great victory, and slew the warlike bishop, and Ælfnoth the sheriff besides. The English army was reduced to terrible straits, when Bishop Ealdred united with Leofric, Ælfgar's father, and Harold himself to pacify the victorious Welshman. Gruffydd 'swore oaths that he would be to King Edward a faithful and unbetraying underking.' An important result of Gruffydd's Mercian alliance was his marriage with Ealdgyth [see Aldgyth], the beautiful daughter of Ælfgar, who, if a later French writer can be trusted, was devotedly attached to him (Benoit de Sainte More, in Chroniques Anglo-Norm. i. 178.) In 1058, when Ælfgar, now earl of the Mercians, was a second time outlawed, Gruffydd and a Norse fleet again succeeded in effecting his restoration by violence. Gruffydd now remained quiet until his father-in-law's death broke his last tie to England.
In 1062 Gruffydd again invaded the borders, and pushed his forces even beyond the Severn (Lives of Edward the Confessor, p. 425). At Christmas Harold was sent with a small force of Norsemen to repel him. Again Gruffydd shirked an encounter, and Harold penetrated to his castle of Rhuddlan in the vale of Clwyd. Gruffydd escaped with difficulty by sea, and Harold burnt his palace, ships, and stores. On 26 May 1063 Harold again invaded Wales, sailing with a fleet from Bristol, and circumnavigating a large part of the Welsh coast. Tostig joined his brother with a land force, which completed the subjection of the Welsh. Gruffydd's old tactics were no longer of avail against Harold's superior forces and strategy. For the whole summer Wales was harried and plundered, until the Welsh grew tired of Gruffydd, and denounced him as the author of their misfortunes. They drove him from his throne and declared him an exile. On 5 Aug. Gruffydd was slain by the treachery of his own men, 'by reason of the war which he waged with Harold the Earl' (A.-S. Chron.). 'His head was brought to Harold, and Harold brought it to the king, and his ship's head and the ornaments therewith.' His widow soon became the wife of Harold. His lands, shorn of considerable portions now incorporated with England, 'were given to his half-brothers, Bleddyn and Rhiwallon, sons of Cynvyn, his
