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Castles & knights

Story of castles

A ruined castleA ruined castle Castles are found in different parts of the world; today, many lie in ruins. Most castles were built hundreds of years ago by rich and powerful people, such as kings or wealthy landowners, to defend and control the land around them. In Europe, the earliest castles, called motte-and-bailey castles, were wooden forts built on the top of a hill. These were soon replaced by castles with stone walls. 

Motte-and-bailey castles

The first motte-and-bailey castles were built from around AD 992. When a baron was granted land by the king, he quickly built a castle on it to defend his new territory from attack. The quickest and easiest way was to build a castle out of earth and wood. Motte-and-bailey castles were the result. A motte-and-bailey castleA motte-and-bailey castleWooden towers were built on top of large mounds of earth called “mottes”. The mounds varied in height from 3 to 30 metres (10–100 feet) in height and from 30 to 100 metres (100–330 feet) in diameter. If there was no natural hill, one had to be built. Hundreds of local men were forced into digging earth and hauling timber.

The tower was surrounded by a high fence, called a palisade, which was plastered so that it looked as if it were made of stone. The lord, his family and his guards lived in the tower. At the base of the motte was the bailey. This open space was protected by a second palisade and a surrounding ditch. It could be used to house people and their livestock in times of war. Inside the bailey were a hall, chapel, grain store and stables. A timber drawbridge linked the motte to the bailey.

A shell keepA shell keep

Shell keeps

Motte-and-bailey castles were soon replaced by stone buildings, which were stronger and not so easily burnt down. In some castles, the motte palisades were simply demolished and replaced by stone walls. Shell keeps first appeared around 1100: these were where thick circular stone walls replaced the old wooden palisades on top
of mottes.

Instead of a tower, the outbuildings and living quarters were built against the inside of the wall, leaving a small courtyard at the centre. The wallwalk, patrolled by guards, was reached by stairways inside the walls.

A rectangular keepA rectangular keep

Rectangular keeps

In the late 1000s and early 1100s, the first rectangular stone keeps, called donjons, were built. These were much stronger and easier to defend. They had several floors, thick stone walls and corner towers. A curtain wall was built around the keep and its bailey, along with a large gatehouse and drawbridge. Outbuildings were built against the inside of the curtain wall.

Rectangular keeps incorporated all the important parts of the castle in one tall building. The floors were linked by spiral staircases in the corner towers. Stores and guards’ quarters were situated on the lowest floor, the Great Hall above that, and the lord’s private rooms and chapel on the top floor.

Rounded, projecting towersRounded, projecting towers

Projecting towers

The development of the crossbow in the 1100s had a major effect on castle design. Although slow to load, they were immensely powerful and accurate. Castle attackers had a new weapon—but, equally, defenders could fight back even more effectively. By the 1200s, curtain walls with projecting towers became standard, giving archers and crossbowmen a better line of sight.

Rounded, rather than, square towers were increasingly favoured, as they gave bowmen on the battlements an even better all-round view of the enemy below. With this kind of defence, the large rectangular keep soon became unnecessary. In many new castles of this period, rooms were built into the towers or gatehouse instead.

Concentric castles

Krak des ChevaliersKrak des ChevaliersBy the late 1200s, a new design became the most common form of castle: the concentric castle. The inner ring of curtain walls was now encircled by an outer wall, built low enough to permit an unobstructed line of fire from the higher inner walls. The idea had come from observing the walls of Constantinople, which knights came across during the Crusades. Krak des Chevaliers, a Muslim fortress in Syria, fell into the hands of the Crusaders. During the 1200s they converted it into a concentric castle by adding an outer curtain wall.

A concentric castle had two rings of curtain walls.A concentric castle had two rings of curtain walls.Attackers attempting to take a concentric castle now came under increased fire and had to break through several barriers if they were to succeed—with the extra risk of finding themselves trapped between two sets of walls. By around 1285, European castles had become almost impregnable strongholds. The only way to capture a castle was by a long siege.




Before the 1300s, wooden structures called hoardings would be fixed to the battlements when preparing to defend the castle during a siege. These were frames that projected from the wall in front of the crenellations and were covered by roofs. Around the 1270s, permanent stone overhangs, called machicolations, began to replace hoardings. The parapet at the top of the castle walls were specially constructed to project outwards from the wall below. In the floor were square holes through which guards could shoot arrows or drop hot sand or missiles on attackers at the foot of the walls.


Cannon firing at a castleCannon firing at a castle

The decline of castles

By the end of the Middle Ages, the power of the noble families had grown weaker. Kings and queens had taken greater control of their kingdoms. Battles between barons were now rarer. Castles were, in any case, costly to build and much less useful as a means of defence. For example, powerful cannons could blast great holes in even the thickest walls. If, during a battle, an army tried to seek protection in a castle, it could not hold out for long.

A 16th-century castle residenceA 16th-century castle residenceSo fewer and fewer nobles built new castles, preferring to live in large houses instead. If a castle had survived undamaged, however, and could be turned into a comfortable home, living in a castle was the height of luxury.


Consultant: Philip Parker


  • c.992
    First motte-and-bailey castles built in Anjou, France.
  • 1066
    Norman Conquest of England. William I builds 87 castles, including square stone towers called donjons or keeps.
  • 1096–1291
    Crusades. Wars between Christians and Muslims from 1096 to 1291. Many castles are built by the Crusaders to protect the lands they won.
  • 1099
    Siege of Jerusalem. The Holy City is won by the crusaders.
  • 1100s
    Keep castles are developed. These have extra walls surrounding the keep tower.
  • 1150–1250
    Major castle building across Germany.
  • 1200s
    Features of crusader castles, such as portcullises and rounded towers, are introduced into European castles.
  • 1272
    The great crusader castle Krak des Chevaliers falls to the Muslims.
  • 1337–1453
    The Hundred Years' War in Europe. Active period of castle warfare.
  • 1429
    Siege of Orleans. Joan of Arc fends off the English besiegers and wins back the French city.
  • 1582–1615
    Great period of castle building by Samurai knights in Japan. Siege of Osaka 1615.
  • 1600s
    Cannons are now powerful enough to destroy the strongest castle walls. Many castles ruined or abandoned. Some turned into private homes, for instance, Saumur Château in France.
  • 1800s
    Castles, such as Neuschwanstein in Germany, built as luxury houses rather than fortresses.

Krak des Chevaliers in Syria was originally an Muslim fortress. It fell into the hands of the Knights Hospitaller, an order of Crusader knights. During the 1200s they converted it into a concentric castle by adding an outer curtain wall. King Edward I of England used it as a model for his own castle builders to follow in the 1280s.

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