Throughout the 6th century frequent references to Alcluyd occur. Again in the Annals of Ulster it is shown that bishops of the Celtic Church were taking their name and style from Dumbarton, As an example, in 554AD the Annals record the death of Cathul MacFergus, Bishop of Alcluyd. At about the same date, in the Episcopus Britannorum, Kentigern, more widely known as Mungo ('the beloved'), is recorded as having gone with his monks from Glasgow to Alcluid, 'where they laboured with great diligence among the people'.