In 1063, at the age of eight, when his father was slain in the battles against the English, Gruffydd was living with his mother, the daughter of the Danish King of Dublin, in Ireland. In 1081, after years of fighting between the various different descendants of Hywel the Good, Gruffydd was victorious at the battle of Mynydd Carn. At that time he assumed control of the kingdom of Gwynedd. In the meanime, however, William the Conqueror had installed the Norman dynasty in England following the Battle of Hastings in 1066. Shortly after assuming the kingship Gruffydd was captured by the men of William's vassal, Hugh the Fat, Earl of Chester, and imprisoned for twelve years. Hugh's cousin, Robert, was apparently, for all practical purposes, the ruler of northern Wales. In about 1094 Gruffydd escaped from prison and regained control of Gwynedd. In 1098 the earls of Shrewsbury and Chester launched an unsuccessful military campaign to remove him from power. Gruffudd consolidated his hold upon Gwynedd and, for decades, he rebuilt the strength of his kingdom. The kingdom of Powys was, during this time separated from Gwynedd. Its rulers henceforth would all be descendants of Bleddyn ap Cynfyn. In the later years of his reign Gruffudd siezed Caridigion and parts of Powys.