Barrow, we should add to the territories named the diocese of Leighlin, which lies between Ossory and Ferns. But there is good evidence that the ancient Fifth of South Leinster was still more extensive. It extended over a considerable part of eastern Munster, taking in almost the whole county of Tipperary and a small part of County Limerick. The territory of Ossory, we are told, stretched from Gabhrán to Grian, _i.e._, from the district of Gowran in County Kilkenny to the district of Pallasgreen in County Limerick. There were several stories which explained how and why this western part of Leinster was transferred to Munster. According to one account Osraige ö Gabrán co Gréin tucad i n-éiric Eterscéil. The territory of Ossory was forfeited to Munster in consequence of the slaying of Ederscél, king of Ireland, father of Conaire Mór. Ederscél was of the Ivernian race. A second account is alluded to by a poem in the Book of Rights, claiming that Ossory was rightfully subject to the kings of Munster, having been forfeited for the killing of Fergus Scannal, king of Munster. The third account is much more elaborate. It is found in the story of the Migration of the Déisi, a story which in its extant form dates from about the year 750. It tells how the Dési were expelled from the region of Tara; how one part of them crossed the sea and settled in Wales; how another part sojourned for a long time in Leinster, but at last entered the service of the king of Munster and acquired a territorial settlement by conquering and annexing to Munster the western part of the territory of Ossory. The story relates that the men of Ossory were first driven eastward over the Suir; they rallied near Clonmel and were again defeated and driven across the Anner; were followed up by the Déisi and finally forced over the Lingaun river, which to this day forms part of the boundary between Ossory and Munster. The baronies of Iffa and Offa took their name and origin from a branch of the Déisi settled in the conquered territory. West of the Suir in County Tipperary are the baronies of Upper and Lower Kilnamanagh. These were formerly O'Dwyer's country, and the territory was ruled by the ancestors of the O'Dwyers from time immemorial. But the line of the O'Dwyers and their forefathers was an offshoot of the ruling people of South Leinster. In the genealogies, Fionn File is their ancestor, the same who was king of South Leinster in Cú Chulainn's time. Of the same Leinster stock came the sept Ui Cuanach, whose name and territory is represented in the present barony of Coonagh in County Limerick, adjoining O'Dwyer's country. On the western side of this territory was the district of Grian, the western limit-point of ancient Ossory.