GRUFFUDD AP CYNAN AND THE HIBERNO-NORSE WORLD GRUFFUDD AP CYNAN was one of the most significant figures of late eleventh-century and early twelfth-century Wales. After a prolonged struggle taking place over twenty-five years, he established himself as the king of Gwynedd. He warded off challenges from both rival dynasties and the Normans and ruled into old age, being finally laid to rest in 1137 after sixty years as a major political figure. R. R. Davies has called his career 'a truly remarkable achievement', especially as it took place during one of the most turbulent periods of Welsh inter-dynastic rivalry.1 Moreover, Gruffudd also had to contend with a new and vigorous challenge to the ancient kingdom of Gwynedd, namely, that of Hugh of Avranches, the Norman earl of Chester, and his ambitious kinsman, Robert of Rhuddlan. Gruffudd's success may seem all the more surprising when we consider that in 1075 he was viewed as little more than a pirate and had barely set foot in the country whose throne he claimed. He undoubt- edly had genealogical claims to the kingship but it is unlikely that these would have amounted to anything but for the support of Hiberno- Norse and Irish troops who were present at all his major battles.2 Their support is indicative of Gruffudd's relationship to the Silkenbeard dynasty, the leading Scandinavian family in Dublin. The influence of this family remained important even after the native Irish conquest of Dublin in 1052.3 It was certainly influential in securing aid for 1 Conquest, Coexistence and Change: Wales, 1063-1415 (Oxford, 1987), p. 44. 2 History of Gruffudd ap Cynan (HGC), ed. and trans. A. Jones (Manchester, 1910), p. 47. 3 S. Duffy notes that Diarmait mac Mael na mB6 gained control of Dublin by backing the Silkenbeard dynasty in a factional dispute. Later Donnchad mac Domnall, while establishing himself as ruler of the city, granted lands to Christ- church, an institution founded by, and closely associated with, the Silkenbeards: 'Irishmen and Islemen in the kingdoms of Dublin and Man, 1052-1171', Eriu, AUII (1992), 93-133, at 96-7,102-4.