The Irish church in the 8th century was insular, secularized, and predominantly monastic. Viking raids beginning in 795 disrupted the church and led to the establishment of the first Irish towns. Norman invasion in the 12th century and English colonization that followed radically changed Ireland, dividing it into Gaelic and Anglo-Irish cultural zones. Irish church reform established a new diocesan structure but discrimination between the Gaelic Irish and Anglo-Irish emerged and racism became institutionalized. While two distinct nations co-existed uneasily on the island, the church remained officially unified.