Siege and fall of Chang'an

The siege and fall of Chang’an turns Ma Chao’s campaign for revenge into a strategic threat to Cao Cao’s control of the north. A siege that fails to break the city directly is transformed by Pang De’s ruse: once the gates open, Cao Cao must redirect his forces to the Tong Pass, and his planned southern campaign is abandoned.

Causes and Strategic Stakes

The crisis begins after Ma Chao learns that Cao Cao has killed his father and brothers. Vowing revenge, he receives a message from Xuande proposing a coordinated attack: Ma Chao should strike from the west while Xuande attacks from the south. Ma Chao agrees, gathers support from other leaders in the region, and leads more than two hundred thousand tribal warriors toward Chang’an.

The governor, Zhong Yao, sends urgent news to Cao Cao and advances against the western army. His first engagement ends in defeat, and he retreats into Chang’an, where Ma Chao’s forces lay siege. The city thus becomes both a refuge for Cao Cao’s governor and the immediate obstacle to the western advance. Its fall would also threaten the wider balance of forces: the attack from the west is intended to prevent Cao Cao’s troops from invading the south.

Pang De’s Ruse and the City’s Fall

After ten days without success, Pang De proposes lifting the siege to draw the city’s inhabitants out. Ma Chao accepts the plan, and the besiegers withdraw into the hills. Once Zhong Yao is convinced that they are gone, he opens the gates. People stream out and return for five days; the movement also allows people who had not previously been inside the city to enter.

The apparent retreat conceals the real attack. Late one night, a fire breaks out by the west gate. Zhong Jin, the gate commander and Zhong Yao’s brother, rides to investigate. Pang De identifies himself and strikes him down. The gate is opened, and Ma Chao’s western troops pour into the city. Zhong Yao escapes and establishes a defensive position at Tong Pass, while messengers carry news of Chang’an’s fall to Cao Cao.

The Consequences at Tong Pass

The capture has the effect Xuande and Ma Chao intended: Cao Cao abandons the southern campaign. Recognizing the importance of holding Tong Pass, he sends ten thousand elite troops under Cao Hong and Xu Huang to reinforce its defence. Ma Chao brings his troops to the pass and repeatedly taunts the defenders into coming out to fight. Xu Huang restrains Cao Hong, who is eager to attack, until the ninth day, when Cao Hong sees the western troops resting and descends with three thousand men.

Cao Hong’s surprise attack scatters Ma Chao’s troops, but his success is short-lived. Xu Huang rides after him to call him back; as the two commanders join up, Ma Chao charges from one side and Pang De attacks from the other. Half of Cao Hong’s men are lost, and Cao Hong flees with Pang De in pursuit. Ma Chao then takes control of the pass. The fall of Chang’an has therefore achieved more than the capture of a city: it has redirected Cao Cao’s campaign and opened the way for Ma Chao to seize a crucial defensive position.