The first bishop of Killala mentioned in Roman records was Donatus O'Bechdha: his possession of the diocese was confirmed in a rescript dated 30 March 1198 by Pope Innocent III. This records the transfer of ancient churches, monasteries and church properties to the jurisdiction of the diocesan bishop. In the process it provides a record of place names in the diocese. Insula Gedig, for example, is Iniskea, an island in Blacksod Bay. Inisgluairibrandani is Inisglora of Brendan. The original monastery on this island was said to be founded by St. Brendan.
