The Domesday Book is The National Archives' oldest and most famous public record. It is a highly detailed survey and valuation of all the land held by the king, William the Conqueror, and his chief tenants along with the resources that went with that land. In 1085 England was threatened with invasion and William needed to know what financial and military aid was available to him. He therefore commissioned a survey to discover who owned what, how much it was worth, and what was owed to him. Summaries of the findings were edited by county into a final volume called Great Domesday. However, it was never finished and the returns for East Anglia remain in draft form in a second volume known as Little Domesday. Together, these tomes consist of 900 pages, two million words, cover 37 counties, and list over 13,000 places. So authoritative did the record become that it was nicknamed 'Domesday' since, just as Christ will have the last word on the Day of Judgment (or 'Doom'), so Domesday has the final word with regard to legal title to the land recorded within its pages.