In the meantime the security of Iona was threatened by new enemies. These were the Norwegian Vikings who occupied the Western Isles about the middle of this century, and continued to do so from time to time, till their permanent settlement in the Orkney Islands, towards the end of the century, led to a more continued possession of the Isles; and in the year 878 it appears to have been necessary to remove the relics of St. Columba from Iona to Ireland for safety. These consisted not only of the _Mionna_, or reliquaries, which had been so frequently taken to Ireland, but also of the shrine which contained the remains of his body; for we are told that in this year ‘the shrine of Colum Cille and all his reliquaries were taken to Ireland to escape the foreigners,’[596] and two years later Feradach, son of Cormac, abbot of Iona, dies.[597] He was, no doubt, the successor of Cellach, the abbot of Kildare, but his pedigree is unknown, and there is nothing to show whether he was connected with any other religious house. The line of Conall Gulban, however, the ancestor of the tribe of the patron saint, now comes in again, but merely to give to the abbacy of Iona its last independent abbot for many a long year. Flann, the son of Maelduin, whose death as abbot of Iona is recorded in the year 891,[598] was a descendant of Conall Gulban; but one of the same tribe, Maelbrigde, son of Tornan, having been in 888 elected abbot of Armagh, the abbacy of Iona seems to have fallen under his rule also, and thus he is described as ‘coärb of Patrick and of Columcille’ in the Martyrology of Donegal, which adds that he was ‘a man full of the grace of God, and a vessel of the wisdom and knowledge of his time.’[599] His death is recorded in 927.[600]