What is the fine-grained topic of the following text: "sons of the followers of St. Canice" were of the Cenel Eoghain group, a collective clan name for tribes descended from Eoghan, son of Niall of the Nine Hostages, the 5th Century High King of Ireland, who were chiefly located in Counties Derry, Tyrone and Donegal. Only return the topic.
The Cenel Eoghain group and their origin in Ireland