Domesday Book was commissioned by William the Conqueror (1066-1087) at Christmas 1085. It was designed to show who held every piece of land in the newly conquered Kingdom of England. It was known colloquially as the Domesday Book because it was seen as being as final as the Last Judgement and as difficult to conceal things from. The book does not cover the whole country - Cumberland, Durham, Northumberland, and Westmorland were omitted and London and Winchester likewise, along with some other towns. A separate book, called Little Domesday covered the counties of Essex, Norfolk and Suffolk and, despite its name, it is actually bigger and more detailed than the Great Domesday Book containing the other counties.

Domesday Book records one manor, or holding, in Sandy, held by a man variously known as Eudo Dapifer, Eudo the Steward and Eudo, son of Hubert. He held twenty seven manors in Bedfordshire as well as other manors in other counties. Sandy was a large manor at sixteen hides, one virgate and had two mills. These would have been on the River Ivel as England had only watermills, no windmills, at that date. The mills together were worth fifty shillings. The manor had been held by Wulfmer of Eaton [Socon?], a thegn of King Edward the Confessor in 1066 when it was worth £10. This had fallen to £8 when Eudo acquired it but had risen to £12 by 1086.

It is suggested by historians that the reason for the general lowering of the value of manors in the area is accounted for by William I's armies coming through Bedfordshire on their way to put down rebellions in the north. They would have lived off the land and no doubt have committed certain acts of vandalism in what was, to them, still alien, even enemy, territory.

The manor also included twenty four villagers, six smallholders and two slaves. These men were heads of household and their number must be multiplied by a factor of at least four to account for wives and children - suggesting a population of about a hundred and thirty or so, quite a good sized settlement for the date.

Domesday Book notes: "Here  Eudo claims three acres of woodland against Hugh Beauchamp, which Wulfmer held; but Ralph dispossessed him when he was Sheriff. Therefore Eudo refused to give the defence obligations from this woodland. This the men of the Hundred also confirm". Eudo was also in dispute with William Speke and Hugh over land in Chawston. It would be interesting to know whether the disputes were resolved amicably, by law, or by the sword. The reference to defence obligations is because landowners had to contribute a fighting man, or part thereof, for each of their estates, based on the size of holding.