The 'Exon Domesday' manuscript is a unique survival from William the Conqueror's Domesday Survey of 1086. It contains complex data on Britain's south-western counties and is one of the regional surveys edited to make the final ('Exchequer') version of Domesday. It is the only such document to survive in tandem with Exchequer.
The manuscript's 532 parchment leaves contain information not found elsewhere, and the entries for the feudal manors are differently arranged and fuller than Exchequer's.
The book is kept in Exeter Cathedral Library, where it may have been brought by Bishop Osbern FitzOsbern of Exeter (d. 1103). He is included as a landowner, and his diocese comprised the whole of Cornwall and Devon. Scholars still have much to learn from Exon, but for many local casual visitors to the library, its main interest lies in the record of their own community in the 11th century.