The first walled cities
The first kind of military fortification was a high wall that would keep enemies from easily entering a village or city. This was beyond what we would call earthworks, or piles of earth beside the ditches they were taken from.
It is no surprise that the earliest civilizations were the first to have walled cities. There were more people and more wealth to protect. As a result, Mesopotamia in the Middle East (5,900 to 3,200 BC), between the Persian Gulf and the Mediterranean, was the first to have walls around its cities. They used sun-dried brick to build them.
As added protection for the governing body, Mesopotamia also created central forts, sometimes called citadels, for the royal family and government officials. Maritime empires like Phoenicia (around 2,500 BC), later on, were always at risk from sea-based attacks. They also learned to wall their cities.
The beginning of siegecraft
As walled cities became normalized, siegecraft, the art of breaking and entering into walled cities, developed. Interestingly enough, there was an extensive lull between the creation of walled cities and the development of siegecraft. One possible reason is that the calculations of building walls are more straightforward. Another is that early techniques of war were usually limited to overrunning a city and overwhelming its human defenses. Walls were a deterrent and a shield.
The first forms of siegecraft would have been the most basic: battering rams, ladders, and scaling ropes. However, the history of military technology shows that more attention was given to arming and training soldiers, instead focusing on military engineering. As a result, through most of the centuries before the Roman empire’s founding in 27 BCE, there was a higher development of personal weapons (like archery) and mounted troops (cavalry), but not so much in military engineering.
The exception was Greece from 400 BCE onwards. At this time, Greece was becoming both militaristic and defensive. It developed two resistance-crushing weapons: catapults of large javelins, and catapults of stones. These could be used to level almost any defense. However, only the catapults of stone would survive past the peak of the Grecian world.
Later, from 200 BCE onwards, the Grecian army created a siege tower that required the strength of 3,400 men to move. With the rise of the Roman Empire, these inventions were not lost. As the Roman Empire grew and spread, the use of catapults and siege towers also continued to grow.
Famous defensive walls
The earliest know high wall fortification was the Great Wall of China, which was put together by the first Emperor of a unified China, Qin Shihuangdi, between 300 and 201 BCE. Because he had the first unified border, the Emperor linked many walled fortifications to create what would become the Great Wall. It was continued and added to for the next 2,000 years.
The Great Wall is often pictured as the product of one continuous blueprint, but that is not the case. Because of the vast border being covered, workers would use local materials. Stone quarries created stone walls. Places with many rivers and much sand used reeds and willows as outer frames, and filled the walls with sand. It is only in the Ming Dynasty (1368-1644) that the brick and limestone parts of the wall were added.
The next set of high, fortified walls as a feat of engineering were the Roman forts and fortifications seen all over the Empire (27 BCE). Part of the feat was the replicable style of the forts, no matter which part of the Empire the fort was found in. A legion, dispatched to its post, could have a temporary wooden palisade, or defensive fence, up in a few hours. The rectangular framework always had a set style and internal arrangement.
If a Roman legion would remain, the fort would be built up with timber, and eventually with stone. More mini-cities and barracks than anything, the most important feature was the watchtower rather than the wall. At least, for most Roman forts.
Where more hostiles were located and more defenses required, watchtowers and forts were linked together by defensive walls. The most extensive and long-lasting of these is Hadrian’s Wall in what is now Great Britain. In the 100s AD, Emperor Hadrian had the Roman troops build a great wall from one side of Britain to the other, to protect Roman territory.
Hadrian’s Wall is partly stone forts and extended defenses, partly earthworks and ditches. It is the 14 forts and their stone extensions that survive, but not much of the earthwork-and-ditch sections.
Medieval forts and warfare
Possibly the most familiar forms of warfare are those concerning medieval forts and castles, as they are dotted all over Europe and featured in movies and stories. Feudal lands and lords gave rise to elaborate houses that were basically glorified forts. However, if we go closer, there are very few innovations they brought that were not already established in the previous eras of military engineering.
- Fortifications and Siegecraft: Defense and Attack through the Ages by Jeremy Black
- The “Bookshelf” of the U.S. Army Corps of Engineers