Aim 1: Students understand how siege warfare operated in the region during the 12th Century.

Aim 2: Students can relate examples of siege warfare to their wider understanding of the period

Siege Warfare in Outremer

Medieval sieges were a difficult affair. The besiegers might suffer crippling casualties without ever capturing the target. They could last months or even years. The besieged were faced with the prospect of a total slaughter should they fail. The fall of Jerusalem in 1099 saw such a bloodbath, as did Baldwin I’s capture of Caesarea in 1101. When Balian of Ibelin negotiated with Saladin in 1187, this must have been at the forefront of his thoughts. Both sides could suffer from flagging moral, disease and starvation. On the Third Crusade, both Richard I and Philip II fell ill at the same time during their siege of Acre. The commander of an attacking army had some difficult decisions to make, largely dependent on their time constraints.

Assaulting a Castle

Sometimes, time was not on the side of the attackers. Perhaps reinforcements were on their way to help the defenders (a consideration at Antioch in 1098 and Damascus in 1148). Maintaining a besieging army, which tended to have to be larger than the defenders’, was difficult. All the soldiers would need feeding and water might be scarce, especially in a region like the Levant. The quickest way into a castle was a direct assault. The weakest part of any castle was the gate. An assault on this directly was possibly with the use of a battering ram. This was usually made from a tree-trunk and could be capped with metal. Men might carry this up to the gate and smash it into this, hoping to shatter it. But a well-built gate would be thick and reinforced with extra crossbeams and metal. Entry would take a while and the soldiers carrying the ram could be shot and pelted with objects whilst doing so. Therefore, wheeled canopies would be constructed to protect the men from projectiles from above. If the defenders tried to burn the whole thing, this could be mitigated by covering the canopy with animal hides soaked in vinegar, which proved hard to ignite. The attackers might also suspend the ram from the canopy with chains to help swing it into the gate with greater momentum.

Threat from rams led to great fortifications being built around a gate, called a gatehouse. This would be higher than the surrounding battlements, with towers that could station many archers to rain arrows down on the attackers. A good supply of rocks might be stored and dropped through holes overhanging the turrets of the towers, known as murder holes. Hot oil, or water, could be poured through these to scorch the attackers too. If oil was used, then a fire brand could be tossed on it to incinerate human flesh and wood! Furthermore, all the towers were built with arrow slits, which provided a negligible target for the attackers, but allowed defenders inside to fire arrows and crossbow bolts at their foes.

If the defenders could not destroy a ram or kill all its carriers, then they still had their portcullis, a metal grate with spikes that could be lowered in front of the gate. This protected the gate itself from the effects of the ram and might even impale the odd unalert attacker. But even if the attackers broke through, they would need to travel through a tunnel in the gatehouse and through to a second gate. Whilst in this tunnel, hell could be unleashed upon them as they would be bombarded from more murder holes and arrow slits, whilst trapped in a confined space that may well not allow their ram’s canopy.

All of this was often too great a task and might only serve as a distraction for the defenders at best. And yet the gate was still the best entry point. This is where the value of scaling a castle’s walls came in handy. The point of getting onto the battlements was not to overwhelm the enemy on the heights but rather for those attackers who succeeded in reaching the top to make their way to the gatehouse, capture it and open the gate for their army. At Antioch in 1098, Bohemund pulled this off without much fighting, owing to the subterfuge of Firouz, the commander of a tower, who helped the Franks onto the walls. But most of the time the battlement had to be won by force.

The attackers might scale the walls via ladders and grappling hooks and ropes. These were risky but could be done quickly and in many places at once. Furthermore, the attacker would use archers to support those climbing the walls. They would shoot anyone who stuck their head over the battlements to try and push the ladders away. These archers could hid behind wooden covers, called mantlets, for their own protection. Ladders were hard to push away anyway, owing to the weight of the soldiers climbing them and the need to push the top much further away than an arm’s reach to cause it to topple. You could make the task even harder by attaching metal spikes to a ladder to help plant it into the ground. That said, ladders had several drawbacks: if loaded to heavily then they might collapse, but if only a few men climbed it they would be very isolated at the top; it was hard to calculate how long to make the ladders; and both hands were needed to climb the ladder and so the attacker could not defend himself well. If the defenders were not content to hack at the attacker once they reached the top, they could attach a grapnel to the ladder and pull it along the wall sideways to hurl it down that way. In the meantime, the towers along the wall were purposely built to be higher than the walls so that the archers in the towers could get a good vantage of the attackers, even if they gained the battlement.

The odds could be better for the attackers if they employed a siege tower, known as a belfry. Some of these were on wheels and could be rolled up to the walls, whilst others were constructed on sight against the walls. Godfrey of Bouillon famously dismantled one overnight and rebuilt it elsewhere at the siege of Jerusalem (1099) and gained the walls that way. These towers would have ladders inside and the attackers would climb to the top whilst shielded from enemy archers, before crossing onto the walls via a drawbridge. Some towers might even contain a battering ram at the bottom and be brought up against the gatehouse. Like a ram, these could be susceptible to flames and other demolition and fire-proofing was never a bad idea. An attempt to burn a siege tower was made at the siege of Ascalon, 1153, although this back-fired (pun intended) in this instance. On the other hand, these took a while to construct and the defenders would hinder this as much as possible. Wood was scarce in the region and on more than one occasion in Outremer, ships were bought for their timber during a campaign. An army would travel too slowly with one, even on wheels, and so these had to be constructed on sight. But a prepared general might bring a kit ready for quick construction.

Overall, an assault on a castle walls was a quick bid for a castle, and a high risk one at that. But in some cases, many options were denied by the defences anyway. Firstly, the terrain a castle was built on might provide sheer cliff faces on several sides that would narrow the options of attack and give the defenders less to think about. Secondly, a castle might be surrounded by a ditch called a moat. Typically, these were surrounded in water but this was hard in the Levant. Even so, a ditch meant that ladders and belfries could not be brought up against the walls and rams could not assault a gate. The defenders would have raised their drawbridge, after all. The attackers might make wooden bridged of their own or fill in the ditch in places but this took time and signposted where an attack was coming from. Other castles solved the problem with a talus: a slope that came out of the wall to stop ladders and belfries reaching the battlements. The most famous was that at Krak des Chevaliers (below), given to the Hospitallers by Raymond II of Tripoli in 1142, which, in this case, was purposely built in a rough, jagged manner so that projectiles thrown down from above would shatter and spray the attackers with shrapnel.

Even if the attackers did gain entry through the walls, victory was far from assured. Firstly, the towers might hold out, with their own supplied and shoot down on the attackers on the battlements and beyond. Secondly, the attackers would enter the bailey: an area where most of the buildings were located that stretched between the outer ‘curtain’ wall and the inner fortifications, known as the keep. The attackers in the bailey could be shot from both sides, with arrows coming from both the curtain wall’s towers and those of the keep. The keep was also the hardest place to take, with taller fortifications on the highest point (sometimes an artificial mound was made). If the castle was particularly well built, its curtain wall might be built in rings, known as concentric walls. Between each ring was a channel that could be shot at from both sides, whilst the attackers attempt to scale a second wall. Belvoir, in the Kingdom of Jerusalem, was the clearest example of this castle type. It was given to the Hospitallers in 1168 by Amalric.

Breaching a Castle

If an immediate victory was not needed but starving the inhabitants into surrender was not an option, a commander would try to make their own entry point by creating a breach in the walls. On possibility was the act of undermining, employed to good effect by Zengi in his capture of Edessa (1144). Special siege engineers, called sappers, would dig a tunnel under the walls, all the while supporting their work with wooden beams. Once a sizeable chasm had been created under a section of the walls, the wooden beams were burnt and the fortification above would hopefully collapse into the space. If the space was not large enough, the walls would hold out, as transpired in Saladin’s first tunnel at Jacob’s Ford, 1179. The defences themselves might be built to try to resist this. For example, a moat would require greater time to dig under. The foundations of the walls might be embedded deep in the ground. Circular towers could also give them more structural stability. If aware of undermining, the defenders might countermine and try to intercept the attackers’ tunnel.

A breach might also be created through the use of artillery. The mangonel was a catapult used by the Franks, who had greater experience in this siege craft than their Muslim opponents. This would hurl boulders at the castle’s walls and slowly fracture the stone work. This relied on enough force and could be easily counteracted by ensuring the walls were thick enough. If a breach started to look likely, the defenders might reinforce the section from behind. These siege engines could also hurl objects beyond the walls. One option was to fling pots of burning oil beyond the walls, which would shatter and spread flames within. Even if the blaze did not engulf the castle, it would keep many of the defenders occupied in firefighting. The attackers sometimes even flung rotting animals over the walls to spread disease within the confined conditions of the defenders.

Nur ad-Din was the first Muslim warlord to make good use of artillery in his siege warfare, followed by Saladin. The latter is the first recorded person to employ the advanced long-range catapult, named the trebuchet. These could fling rocks out of a sling much further than earlier catapults and helped in Saladin’s ferocious bombardment of Jerusalem’s walls in 1187. Their greater range meant that they could avoid being targeted by the defenders, whose walls usually gave them a longer shot owing to the height advantage. But even if a breach occurred, the attackers would be forced through a bottleneck and the defenders would try to hold this narrow opening for as long as possible. Archers on the battlements either side could even shoot at the enemy as they filed into the gap.

Investing a Castle

The process of investing a castle, by which the attackers surrounded a castle and supplies into the castle were cut off, was the least costly option. However, it could only be attempted if time, manpower and resources were on the attackers’ side. The sieges of Shaizar (1138) and Damascus (1148), for example, had to be abandoned, whilst it was desperation at the approach of Kerbogha that convinced the First Crusaders to try a quick entry into Antioch (1098). If the attackers could take their time it would take a large army to entirely block off a castle and stop daring blockade runners from getting past their guards and into or out of the castle with messages and supplies. Castles on the coast would need a naval blockade too, or else they would easily be supplied via the sea.

Without an attack on the castle, the attackers might still speed up proceedings. Negotiation did occur, such as between Saladin and Balian of Ibelin at Jerusalem (1187). If a castle, or more commonly a fortified town, was sourced by a river or stream, the attackers might poison this by dumping excrement into it. However, even if a castle was entirely surrounded, the besiegers might not hold out as long as the defender. The castle of Belvoir, held by the Hospitallers from 1168 onwards, demonstrates this point well. This castle was well equipped for a long-haul defence. Cisterns (water tanks) stored water so that this was not needed from outside sources. Food was kept in cool, dry storerooms so that it would last a long time. The castle had a smithy to help with repairs and the maintenance of weaponry. Meanwhile, attackers outside the walls would need to keep food supply lines open across the difficult terrain of the Levant (food from foraging was scarce) and find sources of water, which were frequently filled in in advance during campaigns. It is no wonder that so many sieges were abandoned. Outremer really was the most influential time and place for the development of Medieval castle building and siege warfare.

Task 1: Match up the definitions and images to the key siege equipment.

Task 3: Use the table attached to fill in the strengths and weaknesses of the siege features included.