Fortifications have existed since before recorded history and the Middle Ages were no different. Forts and castles were used throughout the Middle Ages as a means of controlling territory and could even be used in an offensive manner such as the English under Edward I used in the conquest of Wales in the twelfth century.
Â Â Â Â Â Â Â Â Â Â Â Most of the fortifications used in the early medieval period were Roman works that had survived the fall of the empire. Most surviving Roman fortifications were town walls and even if they did not survive completely they were incorporated into new construction whenever possible.
Â Â Â Â Â Â Â Â Â Â Â The revival of large-scale fortress building can be attributed to the reaction of the Viking invasions in the ninth century. Alfred the Great constructed over thirty forts in England known as burhs to defend against Viking raids. The burh was a simple ditch and rampart fortress and Alfred they were placed no more than a days march apart so that they could be mutually supporting. On the continent several different strategies were employed do deter the Vikings, Charles the Bald of France built a series of fortified bridges in an effort to deny the Vikings freedom of maneuver. They also fortified towns and cities to deny the Vikings plunder. This strategy partially succeeded as the fortified bridges delayed the Vikings providing the towns time to improve their own defensive works.
William the Conqueror made extensive use of the simple motte and bailey castle, which was no more than a mound of earth several meters tall surrounded by a wooden palisade and a surrounding ditch. The motte and bailey castle was able to be constructed quickly and given the state of weaponry at the time could hold out for long enough to be relieved if besieged or constituted a threat in being if bypassed by an invading force. After the conquest of England William parceled out England to his supporters who engaged in a massive castle building program to subjugate the country.
The motte and bailey castle was recognized as an interim solution as its timber construction was degraded over the time by the elements. It is uncertain who began the first stone castle in Europe or when but it has been proposed that Count Fulk of Anjou began the first stone castle in the late tenth century at Langeais in France. These castles were often built on the same sites as motte and bailey castles and sometimes were simply stone versions of the timber structures they replaced. William the conqueror recognized the superiority of stone over timber and constructed some of the first stone keeps in England the best example being the Tower of London
Stone keeps and castles rapidly proliferated in the eleventh and twelfth centuries with Europe becoming dotted with them by 1200. Castle design also changed with many castles using difficult terrain to their advantage by being built on inaccessible crags or on peninsulas. Castle development advanced the most in the Holy Land where castles became great defensive complexes able to be held by small garrisons. The castles built by the crusaders influenced castle building in Europe as returning crusaders incorporated ideas they had learnt in the Holy Land to new construction.
Crusader castle were large complexes enclosing a lot of land such as the great Krak des Chevalier in modern Syria built in the early twelfth century. Krak enclosed an area of 140 x 210 meters and was built on a high hill overlooking the road from Damascus on the site of a previous Muslim fortress. Krak withstood many sieges and was only taken in 1271 when it was manned by an under strength garrison.
Beginning in the fifteenth century castle construction began to change as gunpowder weapons appeared in the battlefield. The high thin walls of traditional castles provided little protection against cannon fire and the search for a solution began. One of the most obvious castle changes due to gunpowder weapons was the addition of gun ports to castle walls. As the technology of fortification improved in the fifteenth century, castles began to get thicker and lower walls until the appearance in the late fifteenth century of the trace italienne, a system of low broad walls and protecting bastions that provided t a viable answer to how to defend against gunfire.
Warship design changed dramatically in the Middle Ages especially along the Atlantic coast of Europe. The round-ship began to be used as a warship in the Atlantic due to its greater sea-keeping ability in rough seas as compared to the shallow draft of the galley. Galleys were used in the Mediterranean throughout the Middle Ages. Galleys were both more maneuverable than round-ships and because of their shallow draft could go many places deeper draft ships could not in the Mediterranean. Galleys were also less dependent on wind than round-ships were.
The round-ship became preeminent in the Atlantic and Mediterranean only after the introduction of cannons for shipboard use in the fifteenth century. They were able to mount more guns than galleys and because of their broad beams were better able to handle the recoil of cannon than galleys were. Improvements in sail arrangements also made round-ships more maneuverable and in some conditions even faster than galleys. After the introduction of the wooden man-of-war in the sixteenth century, galleys quickly faded away in the face of the much superior new ship-type.