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.
France 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.Painter, p ?. These were originally nothing more than towers, donjons (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.
In Languedoc and the south of France, there were more serious attempts, the Peace and Truce of God movements, to curb feudal warfare. But with the spread of heresy came the spread of castles as fortresses to which heretic barons could flee, such as the "five sons of Carcassonne."
Italy In Italy, the process of encastellation is known as incastellamento. It has a specific notion, as the incastellamento describes less the building of castles than the change towards fortified settlements, in which the castle proper (rocca) is a separate part. The term 'incastellamento' for this process was coined by Pierre Toubert.Pierre Toubert: Les structures du Latium médiéval. Le Latium méridional et la Sabine du 9e siècle à la fin du 12e siècle, Rom 1973. As in France, it was a different process in the north and the south.
In the north, the castles were originally the seats of the barons. They spread quickly after the disruption of royal authority in Italy in the mid-tenth century. By the eleventh century, the territorial magnates, like the margrave of Tuscany, were supreme and castles dotted the landscape. With the rise of the city-states after the collapse of Tuscan power in the early twelfth century, the powerful merchant families began to construct fortress and towers as residences in the cities. Well-preserved San Gimignano was the result of the struggle between Guelphs and Ghibellines.
In the centre of the peninsula, the Papal States, the agents of encastellation were not large territorial magnates, but the petty nobles who belonged to various families and factions usually associated with Rome in some way. The Crescentii and the Tusculani constructed fortresses throughout Latium to dominate the roads leading to the Eternal City and the Vatican. During the papal nadir of the tenth and eleventh centuries, their hilltop fortresses gave these minor lords far more power than their territories would otherwise permit. In Rome itself, encastellation often led to the fortifying of the ancient monuments which had fallen into disuses, such as the Arch of Constantine and the Colosseum. These fortresses were usually in the hands of one of the powerful lay families, but sometimes of the popes.
In the Mezzogiorno, the independent principalities of the Lombards and the Italian city-states, which distanced themselves from any central authority, formed an opportune place for the proliferation of castles. Indeed, the nominally Byzantine duchies of Gaeta, Naples, and Amalfi grew around what were originally small coastal fortresses. The decline of ducal authority in these places has been blamed on the tendency to give outlying regions to younger sons (e.g. Docibilis II of Gaeta granting Fondi to Marinus), who then built their own fortresses and thus became independent in fact. Historian G. A. Loud considers incastellamento as one of the chief reasons for the decline in princely influence in Benevento and Capua (especially the former) during the late tenth century.Loud, p 481. Historian Barbara Kreutz notes the encastellation of the monastic estates which dominated south Italian politics and contributed to the constant confiscation and invasion of monastic estates as lay barons sought to increase their power against their foes during the war-filled eleventh and twelfth centuries.Kreutz, pp 134-5. The arrival of the Normans, adept castle-builders, in the early eleventh century only exacerbated the tendency toward fortification of every hilltop. Together with the Prince of Salerno, they subdued Calabria and encastellated its mountainous territory, leading to the inevitable invasion of Sicily.
Spain Encastellation in medieval Spain followed a different pattern from most of Western Europe. Development rather than emerging under similar conditions, it developed in context of the long frontier between the Christian Kingdom and the Muslim polities of Al-Andalus. The construction and occupation of castles on the Iberian Peninsula was linked not only to feudal lordship and aristocratic competition, but also to frontier warfare, territorial expansion, settlement and royal administration during the Reconquista.
the earliest phase of Iberian encastellation began in the eighth and ninth centuries, as both Christian and Muslim rulers fortified vulnerable frontier zones. The Muslims built extensive network of hill forts, castles, fortified citadels and watchtowers to secure communication routes and defend strategic territory. In many areas late conquered by Christian rulers from the eleventh century onwards, these Islamic fortifications were retained, enlarged or rebuilt rather than abandoned, producing a continuity of military landscape uncommon elsewhere in Europe.
Among the Christian Kingdoms, encastellation was especially pronounced in the country and later Kingdom of Castile, whose name comes from the large number of castles established along the frontier with Al-Andalus. During the tenth century, the counts of Castile, particularly Fernán González, encouraged the construction and maintenance of fortified settlements to secure newly occupied territory and protect frontier communities. Castile frequently served as administrative centre from which surrounding district were governed and defended.
Unlike parts of France, where castles were often built by competing local lords, many Iberian fortifications were established under royal authority or with royal approval. the Monarchs of León, Castile, Navarre, Aragon and Portugal integrated castles into broader frontier defense system, using them to control roads, river crossings, mountain passes and newly conquered territory. The growth of castles therefore reflected both military necessity and the expansion of centralised political authority.
Encastellation also accompanied the process of repopulation, where Christian rulers encouraged settlement in conquered territories. Castles became focal points for new towns, whose inhabitants often received municipal charters granting privileges in exchange for military service and frontier defense. this relationship between fortification, colonisation and urban development distinguished much of Iberian encastellation from contemporary developments elsewhere in Europe.
From the twelfth century onwards, the military orders, including the Orders of Santiago, Calatrava and Alcántara and the Knight Templars, became major agents of encastellation in central and southern Iberia. They built, repaired and administered extensive networks of castles guarding frontier districts and strategic routes, while also promoting settlement and agricultural development within their territories.
Regional patterns nevertheless varied considerably. In Catalonia and Aragon, castles formed part of a defensive system of the Spanish March, established under Carolingian influence, whereas in Leon and Galicia many fortifications developed for earlier hilltop strongholds. In the south, numerous Christian castles incorporated or replaced earlier Islamic fortifications, producing architectural forms that combined Romanesque, Islamic and later Gothic military traditions.
By the thirteenth century, following the major Christian conquest of the Guadalquivir valley and Murcia, the strategic frontier moved southward and many earlier castles lost their military importance. Increasingly, castles became centres of seigneurial administration and symbols of aristocratic authority, although frontier fortifications remained significant until the completion of the Reconquista with the conquest of Granada in 1492.
Britain
True medieval castles were a somewhat later arrival in Britain than in continental Europe. The process of encastellation in Britain is as inextricably linked to Normanisation (which is, of course, linked to the Norman Conquest) as the encastellation of Spain is to the Reconquista.
England Prior to the Norman conquest of 1066, English fortification was dominated by the Burh, a commune defensive settlement established under Alfred the great and his successors in response to Viking incursions. Burhs typically incorporated towns and their surrounding population under collective defense, in contrast to the private strongholds characteristic of continental Europe. While certain late Anglo Saxon elites maintained fortified residence, the continental model of the castle, a privately controlled stronghold combining military, administrative and symbolic functions, had not become established in England before 1066.
The conquest inaugurated a programme of fortification subsequently termed encastellation, whereby castles served as instruments of conquest and political consolidation. In the aftermath of the Battle of Hastings, William the Conqueror and his followers erected castles as strategically significant sites throughout England to secure territory, suppress opposition and assert the legitimacy of the Norman regime. Early example were built at points of invasion and communication, including Pevensey, Hastings, and Dover, as well as within major centres such as London, York, Lincoln and Norwich.
The predominant form of early Norman castle was the motte-and-bailey, an earthen mound, either constructed or adapted from existing typography, surmounted by a timber tower, and paired with an enclosed bailey protected by a ditch and palisade. owing to their reliance on local material and labour, such structures could be raised quickly, rendering them well suited to the demands of military occupation. Sites were frequently selected to command settlements, road networks, river crossings and former seats of Anglo Saxon administration.