The construction of medieval Norman Castles began soon after the Norman conquest of England by William the Conqueror in 1066.
The main purpose of the construction of these castles was to quickly establish a power base and consolidate Norman rule throughout England, using a network of castles.
These castles opened a new era in the history of England and castle construction, they were inspired by castles built by the Franks in Francia (Kingdom of the Franks).
According to various estimates of medieval castles by archaeologists, Normans built nearly 500 castles within the first 20 years of the reign of William the Conqueror.
These Norman castles were scattered all over England, although special attention was paid to strategic locations and important towns.
Various improvements were gradually introduced to Normal Castles with the passage of time and after 1070, square towers with four-cornered turrets became popular.
The first castles that Normans built were called motte and bailey castles which in French stands for “clod of earth and enclosure” respectively.
Eventually, round keeps became more popular because it was easier to defend a medieval castle with round keeps compared to square keeps.
Positioning was very important in the construction of a Norman castle. This medieval castle was called a motte castle because it was built on a large mound that could be anywhere between 25 feet and 100 feet in height.
It was also customary to dig a ditch surrounding the motte to make it more secure.
The bailey was the flat land that accompanied the motte and generally ranged from one to three acres. Bailey was also surrounded by a ditch called a fosse.
Hundreds of Norman Castles were built within a few years of the Norman Conquest. One of the earliest built medieval castles after the Norman Conquest was Arundel Castle which had 100 feet high motte and housed the dukes of Norfolk over the subsequent centuries.
The location of Norman Castles was chosen after due consideration of strategic importance. The twin aims of these castles were the defence and control of major towns and cities of England. Thus castles were built in major towns of Cambridge, Lincoln, Warwick, York, and Nottingham. Further, this network of castles also made use of pre-existing sites of Roman and Saxon forts.
The construction of Normal Castles in England ushered in a new era of castle building. Previously, there were very few medieval castles in the country and even those had major defects compared to the latter Norman Castles.
While the first phase of this medieval castle building by Normans was led by the king, subsequently various other castles were built by major magnates and knights on their newly acquired estates.