Castle, a strongly fortified residence. Castles developed in western Europe in the late 10th century as the private strongholds of kings and noblemen and played an important role in the feudal system. Castles were built not only in Europe, but also in the Middle East (during the Crusades) and in parts of the Far East.

A strong castle adequately garrisoned and supplied could be defended for a long time against medieval siege weapons such as the battering ram and the catapult. Even the artillery of the 15th century, while fairly effective against the thin walls of towns, was ineffectual against castles. Only the development of improved cannon doomed the castle as a fortress. The last sieges of castles took place during the English Civil War in the 17th century.

An aura of glamour surrounds the idea of castle life. In reality, however, a castle was a comfortless place. The interior was dark, damp, drafty, and poorly ventilated. The furniture was crude. Soldiers and servants often slept on straw on the floor. Castle life was desirable only in contrast to life in the wretched huts of the peasants and serfs in the village outside the walls.

Many castles have survived to this day. Notable examples include the Tower of London and Windsor Castle in England, Edinburgh Castle in Scotland, the Alcázar in Spain, Château de Pierrefonds in France, Heidelberg Castle in Germany, Krak des Chevaliers in Syria, and the White Heron in Japan.

Early Castles

The earliest castles were made of earth and wood. They were called motte-and-bailey castles. The motte was an earthen mound with a small ditch at its base. The top of the mound was enclosed by a palisade (a wall of vertical wooden stakes) inside of which was a wooden tower. An inclined bridge led to the outer court, or bailey—a flat, circular area adjoining the motte at its base. The bailey was also enclosed by a palisade and small ditch. Except for the Tower of London and Colchester, all the castles built in England by William the Conqueror were of this type.

The first stone castles were known as tours, or towers. The walls of these massive stone structures were as much as 30 feet (9 m) thick. The entrance was well above ground and was reached by a ladder that could be drawn inside. The White Tower in the Tower of London, as originally built, was a castle of this type.

Later Castles

By the late 11th century, some nobles began replacing the palisades on their motte-and-bailey castles with high, thick walls of stone. The palisade and wooden tower on the motte were replaced by a stone tower. This type of tower, called a donjon, or great keep, was the lord's residence. If all other defenses failed, it could be used as a fort.

In the 13th century, stone towers were built to defend the gates leading to the bailey. Later, towers were added along the walls to permit flanking fire against attackers. Wide ditches around these castles were called moats. When the castle was on low ground near a stream, the moat was filled with water, but such castles were comparatively rare. Castles not built near water were often constructed on hilltops or other easily defensible ground. In the late medieval period, many castles became small communities, housing soldiers, servants, artisans, and other support personnel. When the castle lost its military importance during the 16th century, it was displaced as a residence by the more comfortable manor house.