 Sigtrygg was also , according to the Oxford Dictionary of National Biography , " a patron of the arts , a benefactor of the church , and an economic innovator " . In the 990s , he established Ireland 's first mint , in Dublin . He established a bishopric at Dublin and in 1028 he made a pilgrimage to Rome . It is thus possible to attribute the origins of the establishment of territorial bishoprics in Ireland on the Roman model , one of the most important results of 11th @-@ century Irish Church Reform , to Sigtrygg . He went on to found Christ Church Cathedral in Dublin , which today is the oldest building in Dublin , but relatively young in comparison to the many monastic cathedrals in the rest of Ireland . Like many of the other coastal cathedrals in Ireland , it is of Hiberno @-@ Norse origin . The cathedral , initially a wooden building , was rebuilt in stone in the 1180s following the arrival of the Anglo @-@ Normans to Ireland , led by Richard de Clare , 2nd Earl of Pembroke . 
