Construction of the Castle began in 1072 under the orders of William the Conqueror, six years after the Norman Conquest of England, and soon after the Normans first came to the North.
The construction took place under the supervision of the Earl of Northumberland, Waltheof, until he rebelled against William and was executed in 1076.
The castle then came under the control of the Bishop of Durham, Walcher, who purchased the earldom and thus became the first of the Prince-Bishops of Durham, a title that was to remain until the 19th century, and was to give Durham a unique status in England.
It was under Walcher that many of the Castle?s first buildings were constructed. As was typical of Norman castles, it consisted of a motte (mound) and an inner and outer bailey (fenced or walled area). Whether the motte and inner bailey were built first is unknown.
There is also debate about whether or not Durham Castle was originally a stone or a wooden structure. Historic sources mention that its keep (fortified tower) was built of wood, but there is enough archaeological evidence to indicate that even in the late 11th century when it was first built, it had numerous stone buildings.