Cellach (Cellan, or Kellach), a name derived from Ceall, or Cill, "a cell," and borne by thirty-three saints between 657 and 1148; but few of them have much bearing on history, or are distinctly identifiable.
1. Commemorated April 1. Seems to be the son of Sarguse, anchoret, abbot, and bishop of Armagh, in the end of the 9th century. This is likewise the day of Ceallach, abbot of Iona. Ceallach, son of Conghal, was abbot of Hv, A.D. 802-815, and during his presidency the monastery of Kells, in Meath, was founded, or re-organized after its original foundation by St. Columba, and was made the chief station of the Columbian order, on account of the danger and sufferings to which the community at Iona was exposed from the attacks of the Northmen. There is mention also of a Ceallach, son of Conmach, who was blind, deaf, and lame.
2. Deacon in Glendaloch in Ui Mail. Colgan (Tr. Thaum. p. 510,.c. 9) says that St. Kellach, son of Saran, abbot of Fothan (now Fathan, County Donegal), was successor of Mura; died, according to the Four Masters, A.D. 657, and was venerated on October 7. These may have been placed upon the same day, but can hardly be the same person.