Richmond at least as it is known today took shape as a "new town" built around the impressive Norman castle built at the time of the Norman Conquest.
The Domesday Book written in 1086 makes no reference to Richmond and it is may be that little existed prior to the Castle. Attempts have been made however to identify the town with "Neutone" and "Hindrelac" both of which are referred to in the Domesday book.
The Saxon Earls of Mercia prior to the Normans owned extensive estates in this region. They however regarded Catterick and Gilling as their administrative centres. If a pre Norman settlement predated Richmond it was probably of minor importance. That being said several finds of Roaman coins mainly dating from the fourth century have been recorded. Included amongst these finds was a large hoard hidden in a crevice at the bottom of Castle Hill. Perhaps there was an importance to the area, the significance of which has been lost. The existence of Scotts Dyke arguably adds credence to this view.
Following the Conquest William bestowed extensive lands to his followers as a reward for their loyalty. One such award was the vast feudal estate known later as the Honour of Richmond which William granted to Alan (the Red) Rufus, Count of Brittany. Alan was commander of the Breton contingent at the Battle of Hastings and later played a major role in the brutal suppression of the North 1069-1070. This extensive holding, one of the three largest granted by William, was created for military purposes. Not so much as defence against the Scots but rather as an offensive instrument for suppression, conquest and colonisation of Yorkshire. The estate had 199 manors with a further 43 in outlying areas. The Honour of Richmond was a visible symbol that the Norman's were here to stay.
The estate was held by Alan's descendants for most of the next three centuries until Henry IV granted it to Ralph Neville, Earl of Westmorland in 1399. At this point the connection with Brittany was broken.
Richmond as the administrative centre of Alan's estate gradually developed from its essentially military purpose to become a market town.