In 581 CE, the general Yang Jian seized power from the Northern Zhou and established the Sui Dynasty. The Sui reunified China in 589, but the failure of costly expeditions in Korea led to the collapse of the dynasty in 618. The Tang Dynasty reaped the rewards of Sui investments in the empire’s infrastructure to usher in a golden age under emperors Taizong and Gaozong. A rebellion by the general An Lushan in the mid-8th century severely weakened central authority, though the dynasty survived until 907.
The Sui Reunification of China
In 580 CE, Emperor Xuan of Northern Zhou was preparing to launch a campaign to conquer the Chen Dynasty in southern China. The commander of the expedition was Yang Jian, the Duke of Sui, a distinguished general from an aristocratic Han Chinese family in northwestern China.
Although Yang Jian was his father-in-law, the emperor had been suspicious of the Yang family and threatened to depose his empress in favor of another consort. When the Emperor Xuan unexpectedly died, Yang Jian moved to assume the regency in the name of the seven-year-old Emperor Jing. He then defeated an uprising by the general Yuchi Jiong who sought to restore the imperial family’s influence.
In 581, Yang Jian founded the Sui Dynasty and is known to history as Emperor Wen of Sui. He built a new capital near Chang’an and introduced administrative reforms inspired by the Han Dynasty. He was guided by Legalist principles, imposed legal penalties on his own family members for violating the law, and promoted officials based on merit rather than birth.
In 589 CE, the Sui generals Gao Jiong and Yang Su led a campaign against the weakened Chen Dynasty, capturing the Chen emperor and sacking the Chen capital of Jiankang (modern Nanjing). The Sui moved the southern capital to Yangzhou, where the emperor’s son Yang Guang, the Duke of Jin, successfully pacified southern China by showing favor to local Buddhist elites.
Expenditures and Expeditions
In 604 CE, the Duke of Jin became the Emperor Yang upon his father’s death. While the Emperor Wen was responsible for construction of a canal connecting Chang’an to the Yellow River to facilitate the supply of grain to the capital, in 605, Emperor Yang expanded this system to the Yangtze River, creating a nationwide system of waterways known as the Grand Canal. A further branch was constructed in 608 towards the area of modern Beijing in order to supply armies in the northern frontier.
Within months of taking the throne, Emperor Yang established a secondary eastern capital in Luoyang. The city had symbolic significance as the capital of the Eastern Zhou and Eastern Han dynasties, and was also in a strategic position for control of the eastern Yellow River basin. Emperor Yang came under heavy criticism for his lavish spending on his palaces at Luoyang and Chang’an, and the labor obligations involved in the construction of canals and palaces took a heavy toll on the people.
Although the Emperor Yang had a successful military career in southern China and was in nominal command of the Sui forces that conquered Chen, he led three unsuccessful campaigns to subjugate the Korean kingdom of Koguryo between 612 and 614. The failed expeditions triggered a series of uprisings in northern China which the emperor struggled to deal with. In 616, he moved to Yangzhou and left his generals and officials in charge of the north, but was assassinated in 618.
The Rise of the Tang
As the Sui Dynasty collapsed, several warlords competed for power in northern China. In 617, Chang’an was occupied by Li Yuan, Duke of Tang, who founded the Tang Dynasty as Emperor Gaozu in 618. Over the following decade, Gaozu and his sons defeated rival claimants to the throne to consolidate their power and reunite China.
By the early 620s, a rivalry was brewing between Gaozu’s two elder sons, Crown Prince Li Jiancheng and second son Li Shimin. Both had distinguished themselves in the rebellion against the Sui and the subsequent pacification campaigns. While Gaozu made efforts to reconcile his sons, in 626, Shimin killed Jiancheng in a coup at the Xuanwu Gate in Chang’an and took control of the government.
Within a few months, Li Shimin deposed his father Gaozu to become the Taizong Emperor, one of the most effective rulers in Chinese history. Although the Tang Dynasty enjoyed the benefits of infrastructure projects initiated by the Sui emperors, Taizong recognized that such projects placed heavy burdens on the peasantry and reduced labor obligations.
Taizong reversed some of the centralization measures introduced by the Sui emperors and was fortunate to call on the advice of a group of talented officials, who effectively acted as deputies for him on the battlefield and in civil administration. Buddhism flourished during the Tang Dynasty, and between 629 and 645, the monk Xuanzang made a celebrated pilgrimage to India, bringing back a vast collection of Buddhist texts and relics.
Tang Expansion
Taizong’s greatest achievement in foreign and military policy was the conquest of the Eastern Turkic qaghanate. During the mid-6th century CE, the Göktürk qaghanate stretched from the northern Caucasus in the west to Manchuria in the east. By the turn of the 7th century, the Turkic empire was split between eastern and western qaghanates, both of which remained formidable powers.
In the late 620s, a civil war broke out within the Eastern Turkic qaghanate. After allowing both sides to exhaust their power, in 629 Taizong set up a puppet ruler who paid tribute to Chang’an. In 630, Tang armies under the talented generals Li Jing and Li Shiji defeated the Eastern Turks in battle and captured the qaghan. Taizong was subsequently recognized by the Eastern Turks as the heavenly qaghan.
Taizong then set his sights on the Western Turkic Qaghanate, and by the mid-640s, Tang forces had defeated most of the Turkic vassal states in the Tarim Basin. While Taizong died in 649, in 655, his son and successor Gaozong dispatched the general Su Dingfang to lead a new campaign against the Western Turks. By 657, Tang armies successfully conquered the Western Turkic empire and established protectorates to govern the occupied territories. As a result of these campaigns, the Tang Dynasty briefly took control of major Silk Road trading posts in modern-day Uzbekistan and Afghanistan.
Empress Wu
Emperor Gaozong’s 34-year reign was dominated by his consort Wu Zhao, better known as Wu Zetian. As a teenager, Wu had been one of Taizong’s concubines during the 640s, and Gaozong had been so captivated by her that he recalled her to the imperial harem after his father’s death. Her influence at court increased after she gave the emperor a son in 652, and she became empress consort by 655.
Wu quickly moved to eliminate her rivals, and in 657, she designated Luoyang as a permanent second capital, bringing the court closer to her supporters in northeastern China. By 660, she was in effective control of the empire after Gaozong began suffering from an illness which affected his ability to govern.
In 668, the veteran Tang general Li Shiji finally achieved the conquest of Koguryo, though Tang domination of the Korean peninsula lasted little more than a decade. The costly campaign increased popular discontent, and in 674, Empress Wu announced a reduction of taxes and an end to military campaigns to restore popular favor.
Upon Gaozong’s death in 683, Empress Wu ensured that her son succeeded to the throne as Emperor Zhongzong. The new emperor attempted to break free from his mother’s influence, and in 684, Wu replaced him with a more compliant son, Emperor Ruizong. In 690, Wu Zetian took the unprecedented step of becoming an empress in her own right. Despite proclaiming a new Zhou Dynasty, she continued Tang policies and ruled with an iron fist until her health declined and she was overthrown in a coup shortly before her death in 705.
Imperial Overstretch
Wu Zetian’s death was followed by a period of political intrigue during which emperors Zhongzong and Ruizong both returned to the throne. In 712-13, Ruizong abdicated the throne in favor of his son Xuanzong, who introduced reforms to restore political order and revive bureaucratic institutions which had been sidelined during the time of Empress Wu.
Xuanzong’s reign was celebrated as a golden age of Chinese poetry and culture. The emperor himself was an accomplished poet who patronized the arts, and the great poets Li Bai and Du Fu flourished during the period of peace and prosperity that accompanied the first half of Xuanzong’s reign. The emperor was assisted by a group of talented ministers, but from 736, his chief minister Li Linfu accumulated power and began purging his rivals.
The revival of Tang fortunes under Xuanzong enabled China to reassert itself against its regional rivals, particularly the Tibetan Empire to the southwest. While Empress Wu had pursued a defensive policy on the western frontier, Xuanzong’s reign saw a significant increase in military expenditure and the deployment of large armies to the frontier under powerful military governors.
During the 740s, the Tang armies campaigned successfully against the Tibetans and restored their position in Central Asia. In 751, a Tang army under the hitherto successful general Gao Xiaozhi was routed in the Battle of Talas by the newly established Abbasid Caliphate. Meanwhile, Tang forces also suffered a serious setback against the Nanzhao kingdom in present-day Yunnan province.
The An Lushan Rebellion
By the mid-740s, the aging Xuanzong had been neglecting state duties and preferred to spend his time in the company of his consort, Yang Guifei, one of the most celebrated beauties in Chinese history. The emperor promoted members of the Yang family, and when Li Linfu was removed as chief minister in 752, he was succeeded by Consort Yang’s cousin, Yang Guozhong.
After taking office, the new chief minister sought to curb the power of An Lushan, a general of Turkic ancestry who had campaigned successfully in the north at the head of large armies. Despite Yang Guozhong’s efforts, An initially retained the emperor’s confidence, but the general gradually distanced himself from the court.
In late 755, An Lushan launched a rebellion from his base near present-day Beijing, and by 756, he had captured Luoyang and proclaimed the Yan Dynasty. Although the rebels were stopped at the Tong Pass by Loyalist forces, Yang compelled the general Geshu Han to counterattack and advance on Luoyang. Geshu’s army was duly routed, and the rebels marched on Chang’an unopposed.
As the imperial court fled the capital for Sichuan, a mutiny by the palace guards compelled Xuanzong to order the execution of Yang Guozhong and Yang Guifei, and the emperor was soon forced to abdicate in favor of his son, Emperor Suzong. In 757, the Tang general Guo Ziyi recaptured Luoyang and Chang’an, while An Lushan was killed by his son. The rebel forces were not completely subdued until 763.
Revival and Collapse
Following the An Lushan Rebellion, the Tang emperors struggled to restore central authority and provincial governors enjoyed considerable autonomy. The withdrawal of the armies from the northwestern frontier to deal with the rebellion led to the loss of influence in Central Asia.
At the beginning of the 9th century CE, Emperor Xianzong (r. 805-820) made considerable progress in reasserting central authority among the provinces through a series of successful campaigns. However, the centralization process remained unfinished upon Xianzong’s sudden death in 820, commonly attributed to the eunuch Chen Hongzhi.
For most of the 9th century, the Tang court was ridden by factionalism, and the misrule of the late Tang period has traditionally been attributed to the growing influence of palace eunuchs. In spite of this, Tang armies retained the ability to conquer the Uyghur empire in Mongolia in 847.
However, during the second half of the 9th century, the Tang Dynasty faced several major rebellions, the most consequential of which was the Huang Chao Rebellion in 875. Like An Lushan, Huang Chao managed to occupy Chang’an, but his incursion into southern China dealt a fatal blow to the Tang Dynasty’s fortunes.
The rebellion was defeated in 884 by Tang armies led by Li Keyong and Zhu Wen, a former rebel who defected to the Tang. Li and Zhu quickly emerged as the two most powerful warlords in China. In 907, Zhu Wen deposed the Tang emperor and established the Later Liang Dynasty, inaugurating a period of instability known as the Five Dynasties and Ten Kingdoms period.
