Ancient and medieval sieges and siegecraft

Dates c. 7000 b.c.e.-1500 c.e.

Nature and Use

Siege warfare is the art of taking a fort or fortified city. In a passive siege, the besiegers attempted to starve the defenders by sealing off the city or fort from the outside world by circumvallation, which means encircling with a wall or rampart. Active siege tactics assaulted the fortifications by attempting to go over, through, or under the wall. The main weapons and tools for an active siege were ladders for climbing walls, drills and battering rams for punching through walls, and spades for undermining walls. Catapults and siege towers provided support.

Fortifications go back at least to Neolithic times. Seven thousand years b.c.e., the inhabitants of Jericho constructed massive fortifications that included a stone wall 3 meters thick and 4 meters high, a moat 3 meters deep and 9 meters wide, and a stone tower 8.5 meters high and 10 meters in diameter. By the time of the early civilizations in Mesopotamia and Egypt, the art of fortification had already been well developed. Walls featured balconies that allowed defenders to shoot straight down at the enemy, as well as towers and bastions from which defenders could rake besiegers with flanking fire. Gates were the most vulnerable points in a wall, and ancient architects spared no effort to secure them. Pilasters, bastions, towers, and balconies protected them. Metal plating covered the gates to prevent fire. Narrow, winding entryways made it more difficult for attackers to enter the city if they succeeded in breaking through the gate.

Although besiegers undoubtedly circumvallated cities almost from the beginning of siege warfare, the ancient Greek historian Thucydides (c. 459-402 b.c.e.) provides the first detailed account of the construction of a wall of circumvallation in the Siege of Plataea by Sparta and Thebes (429-427 b.c.e.) at the beginning of the Peloponnesian War (431-404 b.c.e.). A mile in circumference, it was a double wall with space between in which to quarter troops. It took two and a half months to build. Battlements and towers strengthened the wall, and the digging of clay for the bricks left a moat on both sides. Plataea was thoroughly isolated but it held out for two and one-half years, revealing the weakness of passive sieges.

To shorten sieges, more aggressive methods were necessary. Escalade, or scaling, was perhaps the earliest means of overcoming fortified walls. A twenty-seventh century b.c.e. Egyptian wall painting at Dehashe shows soldiers trying to pry the gate open with poles while assault teams attack the wall with scaling ladders and archers attempt to drive the defenders from the wall. Escalade was not effective, however, against walls higher than 10 meters. The long ladders needed to scale greater heights were unwieldy and collapsed under the weight of too many soldiers climbing them.

Because walls in ancient Egypt and Mesopotamia rose as high as 20 meters, means other than escalade were necessary to assault them, and battering rams soon came into use. An Egyptian palette dating from around 3000 b.c.e. shows creatures that may be symbolic of battering rams attacking a wall. More clearly, a twentieth century b.c.e. Egyptian wall painting depicting a siege shows three men protected by a mobile hut using a long beam to pry stones from the wall. By the eighteenth century b.c.e. the Assyrians were deploying battering rams in integrated assault tactics that included the use of not only rams but also siege towers, siege ramps, and sapping, a method of undermining walls. Lack of remaining evidence precludes a clear picture of the earliest Assyrian rams, which were probably prying devices used to dislodge bricks from walls. It is not until the Neo-Assyrian Empire in the ninth century b.c.e. that Assyrian rams are seen in palace wall paintings. Assyrian emperor Ashurnasirpal II (r. 883-859 b.c.e.) deployed huge rams that required six wheels for support. A domed turret from which archers could fire protected the front of the ram, and wicker shields also covered the sides and front. The machine was about 5 meters long and from 2 to 3 meters high. The battering pole hung like a pendulum from a rope attached to the roof. It had a metal blade at the end, which the crew could jam between bricks to pry them loose from the wall. The wheels provided mobility, but the ram was so heavy it was difficult to maneuver. Future Assyrian emperors sacrificed weight for mobility, but Tiglath-pileser III (r. 745-727 b.c.e.) used lighter four-wheeled rams that were more maneuverable.

Siege towers were in use in both Egypt and Mesopotamia at least by the early second millennium b.c.e. They rested on wheels or rollers and could be pushed forward into position, providing a means of crossing the wall by dropping a boarding bridge from the tower to the wall. They also gave archers and slingers a better angle of fire to drive the defenders off the wall.

The construction of siege ramps goes back to the third millennium b.c.e. Siege ramps helped attackers cross walls and provided a means of bringing battering rams across moats, outer walls, or slopes at the base of the wall known as glacis. They allowed attackers to attack the wall toward the top, where it was thinner than at the base. Ancient Babylonian mathematics problems show that engineers could calculate how long it would take them to construct a ramp. If these problems reflect reality, the Babylonians could build a ramp to the top of a 22-meter wall in five days with 9,500 men working at the task.

By at least the early second millennium b.c.e. Mesopotamian engineers had developed the art of collapsing walls by sapping. Sapping involved either boring through a wall or undermining it. To undermine a wall, sappers dug a tunnel and then set the support beams on fire to collapse both the tunnel and the wall above. The depth of the tunnel had to be exactly right; if it was too shallow, the weight of the wall might collapse the tunnel on top of the sappers, if it was too deep, it would not collapse when the support beams were burned.

The Assyrians were the first to develop tactically integrated siege armies. Siege warfare was like a giant construction project. The construction of siege towers and siege ramps and the undermining of walls required large amounts of manpower and the ability to organize labor. Assyrian siege armies deployed a variety of skilled troops—sappers, archers, slingers, assault troops, and battering ram crews—and Assyrian commanders knew how to coordinate them toward a common tactical purpose.

Development

The most important development in siege warfare was the invention of the catapult. The first catapult was probably invented by an unknown craftsman under the employ of the Greek tyrant Dionysius I of Syracuse (r. 405-367 b.c.e.). Dionysius had brought a large number of craftsmen from Sicily, Italy, and Greece to Syracuse to manufacture arms for his war against the Carthaginians in Sicily. One of them devised the gastraphetes, or belly bow, which is considered the first catapult. The archer could, by bracing the bow against his stomach, use both hands to pull back a slider with more strength than he could muster with one arm. A trigger, when pulled, then released the arrow. These catapults helped Dionysius take the city of Motya, a formidable Carthaginian stronghold on the west coast of Sicily, in 397 b.c.e. It is probable that winches were added to the gastraphetes early on to pull back the slider with mechanical power.

The next step in the development of catapults was the application of torsion power in which ropes were wound tightly with a windlass. The sudden release of the tension released a powerful burst of energy. Little is known about the origins of the torsion catapult. The Macedonian king Philip II (382-336 b.c.e.) used arrow-shooting torsion catapults that may have been invented by his engineers. Philip’s son Alexander the Great (356-323 b.c.e.) deployed stone-throwing torsion catapults in the Siege of Halicarnassus in 334 b.c.e. Catapults more often strengthened the defense than the offense. For example, in the Roman Siege of Syracuse in 213 b.c.e. the Syracusans used catapults of various sizes to keep Roman ships away from their walls.

In Hellenistic times, siege warfare became more technical and the equipment more complicated. The Macedonian commander Demetrius Poliorcetes (336-283 b.c.e.) employed a huge siege tower called a helepolis, literally translated as “taker of cities,” at the Siege of Rhodes in 305 b.c.e. Protected by iron plates, the tower rose nine stories and was large enough to carry catapults. Twelve hundred men pushed it forward on its eight iron-rimmed wheels. The helepolis provided cover for two gigantic rams. When the helepolis advanced, the Rhodians were able to knock loose some of its iron plating with stone-throwing catapults and set it on fire with flaming arrows shot from catapults. After repairs, Demetrius attacked again. The huge rams did batter down a part of the Rhodian wall, but Demetrius failed to take the city and, in the end, his acceptance of a negotiated end to the siege was a testimony to the difficulty of capturing a well-defended city.

Although the siege equipment of republican Rome was somewhat haphazard, siege machinery was a regular part of the Roman imperial army’s equipment. Each legion was equipped with ten catapults as well as engineers and sappers. A Roman battering ram was a heavy beam with an iron head in the shape of a ram’s head. The Romans used all sizes of catapults. In general Romans seemed to have called their smaller catapults scorpions and the larger ones ballistae, but there was no real consistency in the terminology. Later the word “onager” came into use to describe large catapults. “Onager” means “ass,” and the catapults were so called because of the way the rear kicked up, like that of a donkey, when they were fired. Ancient historian Flavius Josephus (c. 37-c. 100 c.e. ) claimed that Roman catapults were capable of throwing 25-kilogram stones to a distance of 366 meters at the Siege of Jerusalem in 70 c.e. , although he probably exaggerated their range.

Medieval siege warfare evolved little from that of ancient times. The outstanding medieval innovation was the trebuchet, a stone-throwing catapult powered by a counterweight. The throwing arm rested on a pivot so that the end with the counterweight was shorter than the end throwing the missile. When released, the counterweight forced the short end down, lifting the long end with enough force to hurl a stone a considerable distance. The earliest trebuchets used men for counterweights. Several men would simultaneously pull on ropes with all their weight to force down the short end and propel the stone. By the early thirteenth century trebuchets with much heavier dead weights required fifty men to operate them and were capable of throwing a 100-kilogram stone about 150 meters. The biggest Roman catapults could throw a 30-kilogram stone about 225 meters.

Large trebuchets were expensive and relatively rare. In the Siege ofHolyrood (1296) the English king Edward I (1239-1307) deployed three trebuchets, which threw 158 large stones in three days. In 1304 he used thirteen trebuchets to throw 600 stones during the Siege of Stirling.

Despite the impressive array of siege machinery, the reduction of powerfully fortified cities remained difficult throughout ancient and medieval times. Sieges were often time-consuming and expensive. Well-defended, well-provisioned cities could hold out for months or even years. Ancient armies fed themselves by foraging, and when they stopped moving, they soon exhausted food supplies in their immediate area, presenting siege commanders with difficult logistical problems. Siege armies labored in unhealthy circumstances. The disposal of human and animal waste was difficult. Disease was a major killer.

Against this background, psychological warfare was of great importance. Siege commanders tried to intimidate cities into surrendering by offering relatively lenient terms but threatening dire consequences if resisted. The common practices of sacking, rape, transportation, enslavement, and massacre added credibility to the threats.

Ruse and treachery were the preferred means of taking a city. The legend of the Trojan horse reflected the reality that often the only way to gain entry to a city was by trickery. The ancient historian Herodotus (c. 484-424 b.c.e.) tells the story of Zopyrus, a fanatically loyal Persian soldier who mutilated himself so that he could pose as an aggrieved deserter in order to gain entry to Babylon, which was under siege by the Persian emperor Darius (550-486 b.c.e.). Once in the city, Zopyrus opened the gate to the Persians.

Sieges placed cities under great stress, and siege commanders attempted to exploit any social or political fault lines in the hope that traitors would betray the city. This ploy was especially useful in Greek siege warfare. During the Peloponnesian War (431-404 b.c.e.), more cities fell by betrayal than by any other means.

The introduction of gunpowder in the fourteenth century brought an end to a long epoch in siege warfare, which had changed little since ancient times. By the fifteenth century cannon were a regular part of siege warfare for which stone walls were no match. Thus the ancient art of fortification was revolutionized and, with it, the art of siegecraft.

Turning Points

c. 7000

• The inhabitants of Jericho construct massive fortifications around their city.

c. 1900

• Primitive battering rams are depicted in Egyptian wall paintings.

c. 1700

• Assyrians employ integrated siege tactics with rams, towers, ramps, and sapping.

c. 429-427

• A wall of circumvallation is used in the Siege of Plataea by Sparta and Thebes at the beginning of the Peloponnesian War.

c. 399

• The catapult is invented at Syracuse under Dionysius I, significantly advancing the art of siege warfare.

334

• Alexander the Great uses stone-throwing torsion catapults at the Siege of Halicarnassus.

305-304

• Macedonians employ a huge siege tower known as a helepolis during the Siege of Rhodes.

70

• Romans employ catapults during their Siege of Jerusalem.

1304

• English king Edward I employs thirteen trebuchets at the Siege of Stirling.

Bibliography

Anglim, Simon, et al. “Siege Warfare.” In Fighting Techniques of the Ancient World, 3,000 b.c. -500 a.d.: Equipment, Combat Skills, and Tactics. New York: St. Martin’s Press, 2002.

Bradbury, Jim. The Medieval Siege. Woodbridge, England: Boydell Press, 1992.

Campbell, Duncan B. Ancient Siege Warfare: Persians, Greeks, Cathaginians, and Romans, 546-146 B.C. Illustrated by Adam Hook. Botley, Oxford, England: Osprey, 2004.

‗‗‗‗‗‗‗. Besieged: Siege Warfare in the Ancient World. Botley, Oxford, England: Osprey, 2006.

Corfis, Ivy A., and Michael Wolfe, eds. The Medieval City Under Siege. Rochester, N.Y.: Boydell Press, 1995.

DeVries, Kelly. Guns and Men in Medieval Europe, 1200-1500: Studies in Military History and Technology. Burlington, Vt.: Ashgate/Variorum, 2002.

Gabriel, Richard A. “Siegecraft and Artillery.” In The Ancient World. Westport, Conn.: Greenwood Press, 2007.

Kern, Paul Bentley. Ancient Siege Warfare. Bloomington: Indiana University Press, 1999.

Marsden, E. W. Greek and Roman Artillery. Oxford, England: Clarendon Press, 1969.

Yadin, Yigael. The Art of Warfare in Biblical Lands in the Light of Archeological Discovery. London: McGraw-Hill, 1963.