Ending a siege as quickly as possible was always a good idea with both those inside and outside the castle needing to maintain supplies and fend off disease.
The weapons employed to wear down your enemy were as much psychological as physical. What you wanted to do to your enemy was to destroy their morale, their will to fight.
Lobbing the severed heads of captured soldiers over the castle wall – in either direction – was a favoured tactic. This might include the hapless messenger who might have his head send back with the enemy response written on a piece of parchment and nailed to his head.
In 1344, the English were fighting to hold on to Gascony and one of their soldiers tried to break through the French lines with a request for more assistance. He was captured and the poor man was catapulted alive back in to the castle he had sneaked out of.
At the siege of Nicaea in the First Crusade, the heads of Saracens were impaled before the city walls by the crusaders and others catapulted over the battlements. It was quite common to execute prisoners in front of the enemy with a mass hanging calculated to dent morale. Louis VI castrated and disemboweled captives and floated them down the river on barges to be met by their former comrades in besieged Rouen.
One Byzantine emperor blinded a captured Bulgar army save for one in every ten men – who kept a single eye, to lead the others back. When this appalling spectacle returned to the Bulgar king, he apparently dropped dead on the spot (according to the Byzantine telling of it of course).
A similar tactic was used by De Montfort in the crusade against the Albigensian heresy. He cut off the upper lips and noses of a captured garrison and blinded them – leaving some with an eye to lead them to the next castle as a warning of what happened if you resisted De Montfort.
If the enemy began to ram the walls, then they might be discouraged if captured prisoners were dangled – alive – in front of the attacking army. One medieval king attempted to protect his siege towers from attack by mangonels on the city walls by tying live prisoners to the front of the machines.
We talk about ‘human shields’ now in warfare but in the Middle Ages, they were very, very literal. Apparently, this ruse did not work and the siege towers came under renewed attack. One account says that the youths tied to the siege towers died very slowly and “miserably, struck by the stones”.
Those throwing the stones at their captured comrades did so with tears in their eyes. They were horrified at having to attack these young soldiers being used as a human shield. “They crushed their chests, their stomachs and their heads and bone and mushy brain were mixed together”. One can imagine that the defenders might have even tried to hurry the deaths of their comrades by taking special aim at them.
A properly provisioned walled city or castle complex could hold out for up to a year. Day after day they could rain down rocks, boiling oil and arrows on the besiegers. With proper preparation and weapons to hand, it could be the army outside the walls who suffered disease and hunger first and not those holed up behind the battlements.
Life for the besieged might get uncomfortable but with a stiff upper lip (providing you still had one!), you could see off the enemy.