The Domesday Book was a detailed land survey carried out in 1086 by which king of England?

The Domesday Book is a manuscript record of the "Great Survey" of much of England and parts of Wales completed in 1086 by order of King William the Conqueror.

Written in Medieval Latin, it was highly abbreviated and included some vernacular native terms without Latin equivalents. The survey's main purpose was to determine what taxes had been owed during the reign of King Edward the Confessor, thereby allowing William to reassert the rights of the Crown and assess where power lay after a wholesale redistribution of land following the Norman conquest.

The manuscript is held at The National Archives at Kew, London. In 2011, the Open Domesday site made the manuscript available online.

The book is an invaluable primary source for modern historians and historical economists. No survey approaching the scope and extent of Domesday Book was attempted again in Britain until the 1873 Return of Owners of Land (sometimes termed the "Modern Domesday") which presented the first complete, post-Domesday picture of the distribution of landed property in the land that made up the then United Kingdom.