As part of his efforts to secure England, William ordered many castles, keeps, and mottes built – among them thse central keep of the Tower of London, the White Tower. These fortifications allowed Normans to retreat into safety when threatened with rebellion and allowed garrisons to
be protected while they occupied the countryside. The early castles were simple
earth and timber constructions, later replaced with stone structures.
At first, most of the newly settled Normans kept household knights and did not settle their retainers with
fiefs of their own, but gradually these household knights came to be granted lands of their own, a process known as subinfeudation. William also required his newly created magnates to contribute fixed quotas of knights towards not only military campaigns but also castle garrisons. This method of organising the military forces was a departure from the pre-Conquest English practice of basing military
service on territorial units such as the hide .
be protected while they occupied the countryside. The early castles were simple
earth and timber constructions, later replaced with stone structures.
At first, most of the newly settled Normans kept household knights and did not settle their retainers with
fiefs of their own, but gradually these household knights came to be granted lands of their own, a process known as subinfeudation. William also required his newly created magnates to contribute fixed quotas of knights towards not only military campaigns but also castle garrisons. This method of organising the military forces was a departure from the pre-Conquest English practice of basing military
service on territorial units such as the hide .