In the year 1164, Sumarlidi, king of Argyle and the Hebrides, and the community of Iona sent an embassy to Derry to offer the abbacy of Iona to O'Brolcháin, but the king of Ireland, O'Lochlainn, and his nobles, would not consent to his leaving Derry. The Norman invasion made an end of the attempt to organise the Columban monasteries. The Synod of Clane in 1162 ordered that in future only pupils, or as we should now say, graduates of Armagh, were to obtain the position of _fer léiginn_ or chief professor in a school attached to any church in Ireland. This decree then was equivalent to a recognition of the school of Armagh as a national university for all Ireland. I recommend the fact to the notice of those writers who cherish the delusion that Irishmen in that age had no conception of nationality. In 1169, the year of the Norman invasion, the king of Ireland, Ruaidhrí O'Conchubhair, who lived in Connacht, established and endowed in Armagh a new professorship for the benefit of students from Ireland and Scotland. The position of _fer léiginn_ is first noticed in the annals in the tenth century. This points to a new development in the schools of Ireland at that time. Four men holding this position are named in that century by the Annals of Ulster, and three of the four are in the school of Armagh. The fourth is in Slane. In the eleventh century, Kells and Monasterboice have their _fer léiginn_. In Monasterboice that position was held by the poet-historian Flann, who belonged to the ruling family in that region, the Cianachta. In the twelfth century, there are notices of the _fer léiginn_ in Kildare, Derry, Clonmacnois, Killaloe, Emly and Iona. The Norman Invasion brought ruin to all these schools. The last notice of the school or rather university of Armagh is in 1188. Three years before this, Philip of Worcester, king Henry's Justiciary, at the head of a great army, occupied Armagh for a week and plundered the clergy; and Giraldus, who denounces this exploit, says with a jibe, "he returned to Dublin without loss."