Encastellation

Encastellation (sometimes castellation, which can also mean crenellation) is the process whereby the feudal kingdoms of Europe became dotted with castles, from which local lords could dominate the countryside of their fiefs and their neighbours', and from which kings could command even the far-off corners of their realms. The ubiquity of the castle is iconic of the Middle Ages.

The process was rather quick once the castle, as a distinct type of fortress, was introduced. However, it took different forms in different lands. The methods and reasons of encastellation differed based on law (who could legally build a castle), necessity (who needed a castle), and geography (where could castles be effectively built). The stone castle originated probably in the north of France in the tenth century. Older wooden castles, of the motte-and-bailey variety are probably older, though they were far more common until well into the twelfth century.

In France, encastellation began in the north, in Normandy and Anjou, under the direction both of local barons as well as the Duke of Normandy and the Count of Anjou. Most of these castles were of the motte-and-bailey type, which could be constructed with ease in a few months. Stone castles, however, were built before the end of the tenth century in Anjou. These were originally nothing more than towers, donjons (from whence dungeon) or keeps. The reason for this proliferation was to provide oneself with protection in times of war, primarily as a place of refuge, but also as a strategic headquarters: a place from which to sally forth to raid and plunder before retreating to safety (again, the castle). For example, in Normandy:

From Normandy and Anjou, encastellation spread to the Loire Valley. In Poitou, there were thirty nine castles by the eleventh century, the constructions primarily of local magnates. Fortification had briskly increased in Gaul during the Viking Age (see Edict of Pistres) and this merely continued apace while the Carolingian dynasty declined in importance and regional control devolved to regional lords.

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