When we think of ancient warfare, we often picture dramatic battles—armies clashing, arrows flying, and generals shouting commands. But in reality, one of the most challenging and dangerous forms of warfare in ancient China was the siege. As The Art of War wisely put it:
“The method of besieging a city is only a last resort. Constructing siege engines and preparing equipment takes three months. Building mounds and tunnels takes another three months. If the general is too impatient and orders a direct assault, a third of his soldiers will perish without taking the city—such is the disaster of siege warfare.”
Simply put, laying siege to a city was a slow and painful process. It was never the first choice because it required massive preparation and often resulted in heavy casualties. However, a siege didn’t mean non-stop fighting. So what exactly were the attacking forces doing when they weren’t storming the walls?
1. Building Fortifications: Surround the City First, Attack Later
The first rule of siege warfare: cut off the city’s access to the outside world. Without reinforcements or supplies, the defenders would eventually run out of food and be forced to surrender. To achieve this, the attackers would build trenches, walls, and fortifications around the city, essentially trapping the defenders inside.
Take the Battle of Luzhou during the Later Liang Dynasty, for example. The Liang army, rather than launching reckless assaults, focused on surrounding the city with fortifications, completely isolating the Jin defenders inside. Even when Jin reinforcements arrived, the Liang army built additional fortifications to counter them.
And no, this strategy didn’t disappear with the invention of gunpowder. In the Siege of Pingjiang (1366-1368), even with over 2,000 cannons and catapults at their disposal, Zhu Yuanzhang’s forces still dug trenches and built fortifications before attacking the city.
Even in the 19th century, Taiping Rebellion armies used this same technique when besieging towns. They built earthen walls around Xinfeng City to block reinforcements and supplies, turning the city into a helpless island.
2. Digging, Building, and Engineering: Preparing for the Big Attack
Ancient Chinese cities were often protected by massive walls and deep moats. The phrase “golden city, boiling moat” (金城汤池) refers to cities so well-defended that they were nearly impossible to capture. This meant attackers had to spend a lot of time building siege weapons—not an easy task.
One common strategy was to build “earth mountains” or “siege ramps” to allow troops to attack from higher ground. During the famous Battle of Guandu, Yuan Shao’s forces built tall dirt mounds to look down into Cao Cao’s camp and fire arrows from above.
But be careful—rushing construction could be disastrous. In the Tang Dynasty’s attack on Ansi City, an impatient general ordered a siege ramp to be built in a hurry. The structure was so unstable that it collapsed overnight—killing their own soldiers instead of the enemy.
If the attackers had more time, they would construct large siege engines. During the Jin invasion of Kaifeng (1126), the invaders built hundreds of trebuchets (catapults) using tombstones and statues taken from the city’s surroundings. Ironically, just a century later, the Mongols would use the same tactics against the Jin.
And let’s not forget battering rams and siege ladders. The Mongols were particularly skilled at this—during their conquest of Kiev, they forced local craftsmen to build massive battering rams to smash through the city’s gates.
3. Food, Farming, and Logistics: Because Soldiers Need to Eat
“An army marches on its stomach.”
Transporting food was one of the hardest parts of siege warfare. Without a steady food supply, the attacking army would collapse before the city did.
During the Three Kingdoms era, Zhuge Liang invented the wooden ox and gliding horse—a clever device to transport grain over rough terrain during his northern expeditions. But even then, logistics remained a nightmare. The fall of the Sui Dynasty was partly due to Emperor Yang’s failed campaign against Goguryeo, where his supply lines couldn’t keep up with his massive army.
So what if an army couldn’t transport enough food? Simple—they started farming.
Believe it or not, even nomadic Mongols became farmers during their campaigns. The Mongol army had a specialized agricultural unit responsible for growing food during long sieges. When they besieged Xiangyang, they forced local civilians to plant crops outside the city. Some Mongol war plans even included “attack and farm” strategies, where soldiers would cultivate the land while waiting for the city to surrender.
But this wasn’t a new idea. As early as the Spring and Autumn period, when the Chu army besieged the Song capital for nine months, they started building houses and farming outside the city. The Song defenders, hoping to wait out the enemy, were shocked—how could they outlast an army that was growing its own food? In the end, the Song had no choice but to surrender.
4. Training and Psychological Warfare: Messing with the Enemy’s Mind
A siege was as much about mental pressure as it was about brute force. Attackers would often engage in psychological warfare, making life inside the city as miserable as possible.
One classic trick was to starve the defenders psychologically. Even if the city still had food, attackers would release captured civilians back inside, knowing they would increase the burden on food supplies. The Mongols famously did this in their siege of Baghdad (1258), causing chaos inside the city.
Another common tactic was fake assaults—attacking at random times to exhaust the defenders and keep them constantly on edge. The Mongols loved using drums at night, making the defenders believe an attack was coming, only to strike elsewhere when they were sleep-deprived and exhausted.
And then there was spreading misinformation. During the Tang invasion of Goguryeo, the Tang army spread fake news that reinforcements were coming, leading some defenders to surrender out of desperation.
So, Would You Want to Be a Siege General?
If you thought being a siege commander meant just ordering attacks, think again. Siege warfare was a logistical nightmare, requiring construction skills, engineering expertise, farming knowledge, and psychological warfare tactics.
So, next time you play a strategy game or watch a historical drama, remember—the real battle often happened before the first attack even began.