Reachrainn.-Rechru appears to be the correct form. It has not yet been ascertained whether this refers to Lambay, near Dublin, or the island 01 Rathlinn. See note, p. 32, to the "Introduction" to the Wars of the Gaedhil with the Gall.
Mistake.—Ethel. Chron. Pro. book iii.
Irish.—The history of the two hundred years during which these northern pirates desolated the island, has been preserved in a MS. of venerable age and undoubted authenticity. It is entitled Cogadh Gaedhil re Gallaibh (the Wars of the Gaedhil with the Gall). It was quoted by Keating, known to Colgan, and used by the Four Masters; but for many years it was supposed to have been completely lost, until it was discovered, in 1840, by Mr. O'Curry, among the Seabright MSS. The work is now edited, with a translation and most valuable notes, by Dr. Todd. Several other copies have been discovered since, notably one by the Franciscan Brother, Michael O'Clery, which is at present in the Burgundian Library at Brussels. From internal evidence, it is presumed that the author was a contemporary of King Brian Boroimhé. Dr. O'Connor refers the authorship to Mac Liag, who was chief poet to that monarch, and died in 1016, two years after his master. Dr. Todd evidently inclines to this opinion, though he distinctly states that there is no authority for it.
Death.—It appears doubtful whether he really died at this time. It is said that he repented of his sins of sacrilege, and ended his days in penance and religious retirement. See Four Masters, p. 472.