This atlas makes pioneering use of Geographical Information Systems (GIS) to unlock part of the treasure trove of information contained in England's unrivalled medieval public records. The result is an indispensable work of reference. Data from over 9,000 manorial extents, the tax returns of 15,000 individual wills, and 2,000 detailed manorial accounts are linked to reveal the human geography in England during the pivotal 50 years before the Black Death in all its complexity.