At what period of Adamnan’s abbacy he wrote his life of the patron saint and founder of the monastery cannot be fixed with any accuracy, but it was after his visit to Aldfrid in 688; and, as he states that he did so at the urgent request of his brethren, and alludes incidentally to the discord which arose among the churches of Ireland on account of the difference with regard to the Easter feast, it was probably compiled before the same discord had arisen between the brethren of Iona and himself as their abbot.[348] Neither can the precise period be fixed when he founded those churches in the eastern districts which are dedicated to him; but no doubt, after the termination of the Anglic rule over the southern Picts and Scots of Dalriada, he would be desirous to strengthen the Columban Church; and his relations with the kings of the Picts who reigned after the overthrow of the Angles were, as we have seen, cordial and friendly. In this work he appears to have been assisted by the family who had already evangelised the rugged district termed the ‘Rough Bounds,’ as the churches dedicated to them and him are found adjacent to each other. Among the northern Picts, Adamnan’s principal church was that of Forglen on the east bank of the river Doveran, in which the _Brecbannoch_, or banner of Columba, was preserved; and separated from it by the same river is Turriff, dedicated to Comgan. South of the range of the Mounth Adamnan’s most important foundation was the monastery of Dull in the district of Atholl, which was dedicated to him, and to which a very extensive territory was annexed; and closely contiguous to it was the district of Glendochart, with its monastery dedicated to Fillan, whose name is preserved in Strathfillan. Fillan again appears in Pittenweem on the south coast of the peninsula of Fife; and in the Firth of Forth which it bounds is Inchkeith, ‘on which Saint Adamnan the abbot presided.’[349] [Sidenote: A.D. 704-717. Schism at Iona after death of Adamnan.]