The Rise of An Lushan and the Tang’s Vulnerability

The mid-8th century was a period of both splendor and fragility for the Tang Dynasty. Under Emperor Xuanzong’s long reign, China experienced unprecedented cultural and economic prosperity, yet the empire’s military and political structures were weakening. At the heart of this decline was An Lushan, a general of Sogdian-Turkic origin who had risen through the ranks due to his military prowess and the emperor’s favor.

An Lushan’s rebellion in 755 marked a turning point in Tang history. His forces swept through northern China, capturing Luoyang and threatening the capital, Chang’an. The Tang court, paralyzed by factional strife between Chancellor Yang Guozhong and military leaders like Geshu Han, struggled to mount an effective defense. The dynasty’s fate hinged on the strategic Tong Pass, the last major barrier protecting Chang’an from An Lushan’s advance.

The Trap at Tong Pass

An Lushan’s strategy to seize Tong Pass was a masterpiece of psychological and military manipulation. Rather than a direct assault, he exploited the Tang court’s internal divisions. Knowing Emperor Xuanzong’s reliance on faulty intelligence and Yang Guozhong’s distrust of Geshu Han, An Lushan spread misinformation:

– False Weakness: He deliberately left the nearby Shaanzhou region undefended, creating the illusion of vulnerability.
– Court Pressure: Yang Guozhong, fearing Geshu Han’s loyalty, convinced the emperor to order a reckless attack.
– The Ambush: As predicted, Geshu Han’s forces marched into a trap. An Lushan’s troops, hidden in narrow mountain passes, used wind-assisted fire attacks to disorient the Tang army before slaughtering them.

The Tang army’s catastrophic defeat—only 8,000 of 200,000 soldiers survived—sealed Tong Pass’s fate. Geshu Han, captured by his own officer Huoba Guiren, was forced to surrender. An Lushan, ever the pragmatist, executed Huoba for betrayal while briefly employing Geshu Han as a puppet before having him killed.

The Flight from Chang’an

With Tong Pass fallen, Chang’an lay defenseless. The absence of the nightly “peace fires”—signal beacons confirming safety—sent the court into panic. Emperor Xuanzong’s midnight escape on June 13, 756, was a humiliating spectacle:

– Abandoned Capital: Only the imperial family and closest advisors fled, leaving officials and citizens to chaos.
– Symbolic Mercy: Xuanzong refused to burn the treasury or bridges, a rare moment of concern for his people.
– Starvation and Betrayal: The fleeing party, unprepared and betrayed by local officials, resorted to begging for food.

The emperor’s flight shattered the Tang’s aura of invincibility. By the time An Lushan entered Chang’an, the city had descended into looting, and even trusted officials like Eunuch Bian Lingcheng defected.

The Death of Yang Guozhong and the Fracturing of Loyalty

The climax came at Mawei Station, where exhausted soldiers, blaming Yang Guozhong for the disaster, massacred him and his family. The rebellion’s architect was dead, but the dynasty’s legitimacy was irreparably damaged. Key figures like General Chen Xuanli, once Xuanzong’s ally, now saw the emperor as a puppet of corrupt advisors.

Legacy: The Tang’s Fragile Recovery

Though the Tang eventually reclaimed Chang’an, the rebellion’s scars endured:

– Decentralization: Regional military governors gained unprecedented power, weakening the central government.
– Cultural Trauma: The golden age of Xuanzong’s reign was forever overshadowed by the catastrophe.
– Historical Lessons: An Lushan’s manipulation of court politics became a cautionary tale about the dangers of factionalism and misplaced trust.

The fall of Tong Pass was more than a military defeat—it was the unraveling of an empire’s confidence. The Tang survived, but its golden age had ended, leaving a legacy of caution for future dynasties.