A castle was a well fortified building and when the gates were shut and the drawbridge was raised it was a very difficult place for attackers to get into. Medieval soldiers employed many tactics in their attempts to breach a castle's defences. The term siege is defined as the action employed by an army of surrounding a fortified location cutting its inhabitants off from escape or resupply while being attacked.
The attackers, or besiegers, had several types of siege engines that they used in their attempts to break into a castle, but even with the strongest engine a siege could last months. The attackers sometimes had to wait until the defenders in the castle had run out of supplies and surrendered the castle.
Siege Preparations
The besieging army had to protect itself from attacks from the castle's inhabitants and possibly their supporters outside the castle. It was common for the besiegers to construct two lines of defence around the castle. The first line of defences was built between the besiegers and the castle and was known as the circumvallation. The second line, known as the contravallation, was built around the besiegers so that they were surrounded by defensive walls. Both lines of defence consisted of earth banks and wooden palisades. There was a danger that the besiegers themselves would be besieged within their fortifications. Within these lines the besiegers set up their camps and built their siege engines.
Types of Siege Engine
The Trebuchet
This was the largest of all siege engines. It was designed to throw large rocks and missiles at castle walls to destroy them. Trebuchets came in many shapes and sizes, some having wheels so they could be moved around the siege landscape. Trebuchets were built as kits that could be assembled and disassembled and transported in sections to where they were needed. All the pieces slotted together and were fixed with wooden or metal pegs.
A Siege Tower
The siege towers or belfry was designed to allow attackers to get up over the top of castle walls. The tower had wheels so that it could be pushed up to the castle walls and a drawbridge at the top would be lowered when the tower was in place. To protect the tower from fire it would have been covered with animal hides.
The Battering Ram
The battering ram was used to destroy the gates or walls of a castle. It would be hidden under a wooden roof to protect the men who controlled it and mounted on wheels so that it could be moved into position.
The Cat
The cat or sow was a wooden shed mounted on wheels. It had a wooden roof angled so that missiles would bounce off and was covered in animal hides to protect it from fire. The cat would be moved up to the castle with men inside safe from attack from the castles walls. This siege machine was used when a section of the moat needed filling in so that a siege tower could be moved into position. It could also be moved right up to the castle so that the men inside could hack away at the walls in an attempt to weaken them.
The Mangonel
The mangonel was another siege engine that propelled boulders. It had a throwing arm like the trebuchet but worked on a different principal. The arm was slotted through rope so that when the arm was lowered the rope twisted and provided enough energy to make the arm spring back when released.
Trebuchet Game (Beta Version)
Take control of a medieval trebuchet to destroy the enemy castle and capture their flag.
Instructions:
Undermining and defending against it
It was possible to destroy castle walls from above the ground using trebuchets and mangonels but it was also possible to bring castle walls crashing down from beneath the ground. The besiegers employed skilled miners who could construct tunnels starting from their camps and ending beneath the castle walls. Under a section of wall the miners would remove the foundation stones replacing them with wooden props. Once enough of the wall had been removed a fire was lit beneath the wooden props and the miners left the mine. When the props burnt through there was nothing holding the castle wall up and it would collapse. The corners of square castles were the weakest part of the construction and this is where the miners would aim to tunnel beneath.
Undermining and defending against it
Tactics to counteract undermining
Year/Location | Details |
1068 Exeter |
Harold's mother Gytha and her forces still had not submitted to William the Conqueror's rule. They refused to pay the taxes that William demanded and held out at Exeter until their defences were broken. |
1069 York |
An army sent by Sweyn of Denmark landed in the north and captured York. Local rebels joined the Danes and attacked the two castles within the city. |
1093 Alnwick |
Malcolm III, the king of Scotland, and his son Edward were both killed at the battle of Alnwick in Northumberland. Malcolm had invaded England after William II had made moves to take more control over Cumbria and had fortified Carlisle. |
1141 Winchester |
Matilda's forces were besieging a royalist held castle at Wolvesey near Winchester and were attacked and defeated by a royalist relief army. |
1142 Oxford |
Oxford was besieged by King Stephen trapping Matilda inside the city. But just before Christmas Matilda managed to escape across the snow and ice of the frozen Thames dressed in white so that she would not be seen. |
1187 Jerusalem |
Jerusalem fell to the Muslims and the al-Asqu mosque was returned to Islam. The Muslims allowed four Christian Priests to hold services in the Church of the Holy Sepulchre. |
1191 Acre |
Under King Richard's command, the city of Acre is taken back by the Crusaders. |
1192 Jaffa |
When King Richard left Jaffa Saladin took his army out of Jerusalem and attacked the city. After three days of assault the walls of Jaffa fell and the Moslems entered. |
1199 Chalus |
King Richard besieged the castle at Chalus where some treasure had been unearthed. Richard believed it was his and tried to take the castle. |
1216 Rochester Castle |
Invited by the barons opposed to king John, Prince Louis of France landed in England to claim the English Throne. Louis captured Rochester Castle after a short siege. |
1217 Mountsorrel Castle |
Royalists besieged the French controlled Mountsorrel Castle in Lincolnshire. When Louis sent reinforcements to assist those in the castle the royalists moved away to Nottingham. |
1296 Berwick |
King Edward ordered his army to attack the badly fortified town of Berwick. Many Scots were killed in the two days of the attack and possibly somewhere between 7000 and 17000 men, women and children were slaughtered. |
1304 Stirling |
Edward began a siege of Stirling Castle. |
1313 Stirling Castle |
Stirling castle was still under the control of English forces but was under siege from the Scots led by Edward Bruce. |
1333 Berwick |
After the defeat of their relief force at Halidon Hill the day before, the Scots holding out in Berwick had no option but surrender to the English and Edward III. |
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