The theft (and eventual recovery less its golden cover) of the Book of Kells is recorded in the Annals of Ulster under the year A.D. 1007.
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The Great Gospel of Colum Cille was wickedly stolen by night from the western sacristy in the great stone church of Cenannas. It was the most precious object of the western world on account of the human ornamentation (?). This Gospel was recovered after two months and twenty nights, its gold having been taken off it and with a sod over it.
— Annals of Ulster, U1007.11.