A new interpretation of the survey behind Domesday Book — the record of conquered England compiled on the orders of William the Conqueror in 1086 — has emerged from a major new study of the survey’s earliest surviving manuscript. Research published in the English Historical Review shows historians now believe Domesday was more efficient, complex, and sophisticated than previously thought. The survey’s first draft, which covered England south of the River Tees, was made with astonishing speed — within 100 days. It was then checked and reorganised in three further stages, resulting in the production of new documents, each carefully designed for specific fiscal and political purposes. The iconic Domesday Book was simply one of several outputs from the process.