The Crumbling Empire: Tang’s Final Glimmer

The New Book of Tang’s “Biographies of Rebellious Ministers” lamented: “When the Tang fell, all its bandits were born during the Dazhong era (847-860). The virtuous legacy of Emperor Taizong had long departed from the people!” This piercing observation captures the paradox of Emperor Xuanzong’s reign—a period hailed as the “Dazhong Restoration” that secretly incubated the dynasty’s demise.

Born Li Yi, the thirteenth son of Emperor Xianzong, the future Emperor Xuanzong (Li Chen) spent 26 years pretending to be mute to survive the deadly court intrigues of four successive emperors. His act was so convincing that his nephew Emperor Wuzong openly mocked “Uncle Guang” (Li’s princely title) at banquets. Yet when Wuzong lay dying in 846, eunuchs seeking a puppet elevated this “harmless fool” to the throne—only to discover a shrewd ruler who studied Taizong’s governance classics and mastered psychological control over ministers. Officials reported trembling before his unpredictable shifts from stern interrogations to casual chatter about palace gossip.

The Great Collapse of Rival Empires

While Li Chen maintained stability, Tang’s survival owed less to his governance than to the spectacular collapse of its rivals—the Uyghur Khaganate and Tibetan Empire—both unraveling during his reign through self-inflicted wounds.

The Uyghurs, having grown fat on Tang subsidies since helping suppress the An Lushan Rebellion (755-763), fell in 840 when their general Jie Lu Mohe invited 100,000 Kyrgyz cavalry to sack the capital. The settled Uyghur elite, addicted to Chinese luxuries, were slaughtered in their palaces. Survivors split: some migrated south into China proper, while others founded the Ganzhou and Karakhoja kingdoms in Xinjiang—the latter becoming ancestors of modern Uyghurs.

Tibet’s fall was even more dramatic. After two centuries of Buddhist-Kingship synergy since Princess Wencheng’s arrival (641), zealot King Tritsuk Detsen imposed “Seven Households Per Monk” taxes and brutal protections for clergy (“gouge eyes for rude glances”). His anti-Buddhist brother Langdarma seized power in 841, unleashing genocide against monasteries—only to be assassinated by a monk in 842. Civil war between Langdarma’s sons shattered Tibet into warlord fiefdoms, mirroring Tang’s own节度使 (jiedushi) system.

Zhang Yichao’s Impossible Rebellion

Amid this regional chaos emerged Zhang Yichao (799-872), a敦煌 (Dunhuang) aristocrat who witnessed Tibet’s brutal occupation of the Hexi Corridor. The Tibetans forced water-starved oases to grow rice—a luxury crop consuming 3x more water than millet—while diverting Silk Road wealth to Lhasa. By 848, with Tibet’s armies decimated by civil war between warlords Lon Bönskal and Shang Bibi, Zhang rallied Han and allied tribes to reclaim eleven prefectures from Gansu to Xinjiang.

His campaign was a masterpiece of timing:
– 848: Captures Shazhou (Dunhuang) after Tibet’s garrison collapses
– 849-851: Expands eastward as Lon Bönskal’s forces self-destruct
– 863: Finally retakes Liangzhou after 12 years of rebuilding

The Tang court, unaware of Zhang’s initial victories until 850, could only rubber-stamp his achievements. Emperor Xuanzong boastfully declared: “I’ve recovered 3,000 li of territory!”—though the real credit belonged to Zhang’s归义军 (Return-to-Allegiance Army).

The Bitter Aftermath

Zhang’s 867 retirement to Chang’an marked the beginning of the end. The Tang court, paranoid about strong frontier governors, deliberately weakened the归义军 by:
1. Promoting Uyghur and Tibetan remnants as counterweights
2. Withholding material support—forcing Zhang’s successors to defend the corridor alone
By 890s, only Dunhuang and Guazhou remained under Han control. Zhang’s grandson Zhang Chengfeng’s short-lived “Western Han Golden Mountain Kingdom” (910-914) ended in vassalage to Ganzhou Uyghurs. The final曹氏 (Cao family) regime lasted until 1036, when Western Xia absorbed the last Han outpost.

Why the “Restoration” Was a Mirage

The Dazhong era’s apparent stability masked fatal cancers:
– Eunuch Metastasis: Despite Li Chen’s reforms, the “Four Honors” eunuch clique controlled military appointments and taxation
– Regional Explosion: 858-860 saw mutinies across Hunan, Jiangxi, and Zhejiang—where rebel Qiu Fu’s 30,000-strong revolt required elite cavalry to suppress
– Economic Cannibalism: As memorialist Zhang Qian warned, provincial governors inflated “surpluses” by starving soldiers and peasants, creating tinderboxes

When Li Chen died in 859 (possibly from alchemical poisoning), the system imploded. Just as An Lushan’s rebellion began in the southwest (751), the final deathblow came from another southern frontier—Nanzhao’s invasions (859-863) that bled the Tang dry.

Legacy: The Heroism of Holding On

Zhang Yichao’s story embodies the tragedy of late Tang loyalists—brilliant leaders who bought time for a regime too rotten to save. His归义军 preserved Chinese culture in the northwest for two extra centuries, creating the Dunhuang manuscripts that now illuminate medieval history. Yet the dynasty’s institutional decay ensured even such heroism could only delay, not prevent, the coming Five Dynasties chaos.

The real lesson lies in the New Book of Tang’s verdict: empires fall not when challenges arise, but when their systems make heroes’ efforts futile.