Early Tang Power: From the Saddle to the Mirror

Prologue: Zhaoling, the Six Steeds

Late in his reign, the emperor Taizong chose how he wanted to be remembered. He did not order stone copies of his law code or pictures of his palaces for his tomb. He ordered horses: six stone reliefs, carved between 636 and 649, of warhorses he had ridden in the wars that founded the Tang dynasty. They stood at Zhaoling, his tomb on a mountain northwest of the capital, Chang’an. Four are now in the Beilin Museum in Xi’an; two, including the most famous, are in the Penn Museum in Philadelphia.

That famous relief shows a horse named Saluzi, “Autumn Dew.” In 621, during the fighting near Luoyang, an arrow struck Saluzi in the chest. In the stone, a general named Qiu Xinggong stands at the horse’s side and pulls the arrow out. The sculptor did not show an enemy being cut down. He showed care, courage, and loyal service. Carved years after the battle, the relief is not a snapshot. It is a designed monument with a message: this emperor won his throne on horseback, and good men stood beside him. It leaves out how he actually took the throne, the day he had to buy off an enemy army outside his own capital, and the war he could not win.

Behind the monument lies a puzzle. The Sui reunited China and fell apart in thirty-seven years. The Tang, founded in 618 by men from the same ruling class using many of the same institutions, lasted nearly three centuries. What did the early Tang do differently? To find out, we will follow one man, Li Shimin, who became Emperor Taizong, through six places: a saddle, a gate, a bridge, a mirror, the steppe, and a fortress.

The answer can be put in one sentence. Swords won the Tang its empire; cooperation kept it. Where victory could not be turned into cooperation, Tang power stopped.

Place 1 · The Saddle: Winning the Empire

Insiders, Not Outsiders

Li Yuan, the Sui governor at Taiyuan in modern Shanxi, was no rebel from the margins. His family belonged to the Guanlong elite, a network of intermarried military and officeholding families rooted around the passes (guan) near Chang’an and the Long region to the west, many of whom had served the Northern Zhou and the Sui. “Elite” here does not mean a single ethnic group; like the Sui founders, these families came from a mixed northwestern world shaped by both Chinese and steppe traditions. Li Yuan was even family to the Sui: his mother and Empress Dugu, wife of the Sui founder Wendi, were sisters.

In 617, as rebellion spread, Li Yuan rose in revolt. He sought help from the Türks, the great power of the northern steppe, and marched on Chang’an, which fell at the end of the year. Like other strongmen, he placed a young Sui prince on the throne as a puppet. In 618, after Yangdi was murdered at Jiangdu (the final scene of the last lecture), Li Yuan set the prince aside and proclaimed the Tang. He is remembered as Emperor Gaozu.

Very little changed at the top. Most of the new court’s highest officials had served the Sui, and a majority of the chief ministers were related by marriage to the Tang or Sui ruling houses. Gaozu kept the Sui ministries and boards, court control over local appointments, and Chang’an as his capital. A new dynasty had taken over an existing capital, ruling class, and set of institutions.

Proclaimed in 618, Won by 628

A dynasty can announce its beginning in a day, but it cannot make rivals disappear by announcement. In 618 other warlords held most of the old Sui empire. Two of the strongest were Wang Shichong at Luoyang and Dou Jiande on the northeastern plain.

Li Shimin, Gaozu’s second son, became the family’s best general. From 620 he besieged Luoyang. In the spring of 621, Dou Jiande marched to rescue Wang, hoping to crush the Tang army between them. Li Shimin gambled: he left part of his force at Luoyang and blocked Dou at Hulao Pass, a narrow route east of the city. He waited until Dou’s army was tired and disordered, then struck with his cavalry. Dou was captured, and Wang, seeing no rescue coming, surrendered. In one campaign the Tang removed its two greatest eastern rivals. This is the fighting in which Saluzi took the arrow.

The war was not over. Resistance in Hebei lasted until 623, most major southern rivals fell by 624, and the last major holdout, Liang Shidu in the north, fell only in 628. So the shortcut “the Tang reunified China in 618” is wrong; 618 marks the founding, and reunification took another decade. Bargaining mattered as much as battle. The Tang usually treated surrendered rebels leniently, absorbed their soldiers, and often confirmed their leaders in office. Keep that pattern in mind: it returns on the steppe after 630.

Place 2 · The Gate: Taking the Throne

The Best General Was Not the Heir

By 626 Li Shimin had won the wars, commanded loyal officers, and earned an enormous reputation. But he was the second son. The heir was his older brother, Li Jiancheng, the crown prince, meaning the son officially chosen to inherit the throne. Jiancheng and a younger brother, Li Yuanji, feared Shimin’s power and his followers, and the court split into rival camps.

On 2 July 626, Li Shimin and his men waited in ambush at the Xuanwu Gate, the northern gate of the palace in Chang’an. When Jiancheng and Yuanji rode toward the gate, both were killed; the traditional account says Li Shimin shot his older brother himself. The brothers’ ten sons were then executed, removing rivals from the next generation. Li Shimin was named crown prince, and on 4 September 626 Gaozu abdicated, meaning he gave up the throne. Li Shimin became Emperor Taizong.

The violence should not be softened. The “Reign of Good Government” began with the murder of two brothers and their children. The tomb remembered loyalty on the battlefield; this gate is where loyalty inside the family broke.

Who Wrote the Story?

Almost everything we know about the coup comes from histories compiled under Taizong and his successors, which often portray Li Jiancheng as unworthy and Li Shimin as the dynasty’s necessary savior. Taizong took a close interest in that record. In 643 he insisted on reading the draft official history of his reign, something emperors were not supposed to do, and had the account of 626 rewritten to present the killing as a righteous act that saved the state.¹

As early as 1941, the historian Woodbridge Bingham argued that the official histories enlarged Li Shimin’s role in the founding and shrank his father’s; Denis Twitchett later showed how such rewriting worked. Historians today separate the basic events, which are not in doubt, from the moral explanation offered by sources written for the winner. The same caution applies to pictures: the best-known portrait of Taizong was painted in the Ming dynasty, some seven hundred years later.

Place 3 · The Bridge: Facing the Türks

Only weeks after the coup, a new danger appeared. The Eastern Türks were a Turkic-speaking empire of the Mongolian steppe, the vast grassland north of China. Their supreme ruler held the title qaghan, a grander title than the familiar English word “khan.” In September 626, Illig Qaghan led a large cavalry army south to the Wei River, a short ride north of Chang’an.

According to the traditional account, Taizong rode out to the riverbank with a small escort and spoke to the qaghan across the water. Days later the two sides sealed a truce at the Bian Bridge, and the Tang sent valuables to persuade the Türks to go home. The histories stress Taizong’s courage. The payment is the less flattering part of the story, and the more revealing one.

Relations were already tangled: Gaozu had sought Türk help in the civil wars, so the Tang depended on the Türks even as it feared them. The new emperor could kill his brothers inside the palace. He could not yet defend his capital by force.

Place 4 · The Mirror: Learning to Rule

A man who wins a throne by force still has to govern. The fourth place is a mirror, the lecture’s symbol for the cooperation that makes power last. It works at two scales: at court, where a ruler needed people to tell him what power hides, and in the villages, where the state had to see its people to tax them.

The Rival’s Adviser

The mirror begins with a person. Wei Zheng had served Crown Prince Li Jiancheng and had reportedly urged him to move against Li Shimin before Li Shimin moved first. After the coup, Taizong could have executed him. Instead he brought Wei into the new government.

Wei became famous for remonstrance: formally telling a ruler, often to his face, that a decision is wrong. He criticized the emperor’s spending, temper, and plans, sometimes bluntly, and Taizong did not always take it well. But keeping a former enemy’s adviser close told everyone who had served the losing side that the new emperor wanted their talent and honesty, not just their silence. Taizong also balanced regional groups within the aristocracy so that no faction dominated. In Britannica’s words, what made his reign distinctive was not new institutions but “the atmosphere of his administration.” The reason was practical as well as moral: no one man could see everything in a huge empire, and many of his ministers had watched the Sui ignore warnings and collapse.

Tang mirrors were polished bronze discs. A bronze mirror shows outward appearance; history shows how dynasties rise and fall; an honest person shows a ruler his present mistakes. The saying praises criticism, but it also presents Taizong as wise enough to accept it. The Old Book of Tang was compiled in the tenth century from earlier court records, so it preserves a court memory, not a recording.

The ideal was not always followed. Within months of Wei’s death, Taizong, angered by reports about Wei’s conduct, had the memorial stone he had written for Wei’s tomb knocked down. Remember that stone; it reappears at Ansi. Nor was the Zhenguan court democratic: its advisers came from a narrow elite, and the emperor could ignore them. What it offered was a model of a strong ruler protecting honest criticism, a model later officials cited for centuries.

From Court to Village: Registers, Land, and Taxes

Now leave the palace for a farmyard. Picture a county clerk with brush and scroll, writing down each member of a farming household, with age, sex, and legal status. That record decided who could receive state land and who owed grain, cloth, labor, or military service. Registration did not simply count people; it made households visible to the state.

The Tang kept modified versions of systems inherited through the Sui. Under the equal-field system, eligible registered people, above all adult men, received the use of state land by rules based on age, status, and region; part of a grant returned to the state when the holder grew old or died, and part could stay with the family. In return, households owed a set of duties historians call zu-yong-diao.

Two points keep this table honest. First, the duties fell mainly on registered adult men, but the cloth came from women’s weaving: the tax system depended on women’s work. Second, the rules on paper were never enforced everywhere. Powerful families hid dependents, people fled the rolls, and the south was hardest to count; equal-field allocation was probably never enforced there at all. Taxes were also the same for rich and poor, so they weighed most on the poor. Still, the framework lasted until the An Lushan rebellion, the subject of Lecture 5.

Farmers in Uniform: The Fubing

The register also produced soldiers. Under the fubing system (often translated “garrison militia”), several hundred local regimental headquarters organized part-time soldiers. Men were chosen partly for strength, household resources, and the number of adult males in the family. At home they farmed and trained; units took short turns guarding the capital. In wartime the court formed a temporary army under an appointed general, and when the campaign ended, everyone was supposed to go home. In return for tax exemptions, fubing soldiers supplied much of their own equipment and food, and their households kept the farm running while they were away.

The regiments were concentrated around Chang’an and the northwest, and they were never the Tang’s only soldiers: the court also used conscripts, frontier troops, professional guards, and allied steppe horsemen. The system kept armies cheap and kept generals from building private forces. But it depended on short wars.

Rules, Examinations, and Books

Law. Officials far from the emperor needed shared rules. Gaozu’s government issued a Tang code in 624, building on Sui law; Taizong’s court revised it in 637, reducing some severe penalties; and after a new version under Gaozong, an official commentary in 653 explained how to apply it. It is the earliest Chinese penal code preserved in full, not China’s first law code. It also expressed hierarchy, since the same act could carry different penalties depending on family and status, and it became a model for law in later dynasties and in Japan, Korea, and Vietnam.

Examinations. Government schools taught the classics to a small pool of students, mostly officials’ sons. Examinations such as mingjing (“understanding the classics”) tested knowledge of the Confucian classics, while jinshi (“presented scholar”) tested literary composition and questions on government. The route into office was real but not equal: the jinshi passed only a few dozen men in a typical year, family privilege and recommendations still filled many posts, and the exams often helped well-prepared sons of elite families rise faster. Lecture 3 meets that elite.

Texts. Taizong’s court sponsored an approved commentary on the classics under the scholar Kong Yingda, the Correct Meaning of the Five Classics, issued in 653, which gave schools and examinations a shared reference. It also compiled official histories of recent dynasties, including the Book of Sui that shaped the portrait of Yangdi you met last lecture. That is the “past as a mirror” at work, and a reminder that the Tang wrote the record of both Yangdi and Taizong.

Place 5 · The Steppe: Heavenly Qaghan

From the Bridge to the Winter Raid

Remember the Wei River in 626. Four years later, the qaghan who had threatened Chang’an was Taizong’s prisoner. Much of the change happened on the steppe itself. Between 627 and 629, the Eastern Türk qaghanate suffered harsh winters that killed livestock, revolts by peoples it had ruled, and challenges from rival coalitions such as the Xueyantuo. For a herding empire, dead animals meant hunger and lost power. Taizong’s court allied with these discontented steppe leaders. Then, early in 630, General Li Jing led a surprise winter campaign that shattered Illig Qaghan’s camp. Illig was captured and brought to Chang’an, where he lived as a captive until his death a few years later.

The leap from 626 to 630 invites a simple story about Taizong’s genius. A better explanation combines leadership with timing, weather, and steppe politics: the Tang won by entering an existing crisis and building alliances, not by defeating an isolated army.

Two Titles, One Ruler

In the spring of 630, assembled steppe rulers and envoys asked Taizong to accept the title Heavenly Qaghan (tian kehan). “Heavenly” may echo the steppe sky god, Tengri, while also sounding like the Chinese emperor’s title “Son of Heaven.” (The course textbook’s “Great Khan of the Turks” loses that double meaning.) Taizong now confirmed the successors of steppe rulers and issued orders under both titles. One ruler could speak in more than one political language. The title did not turn Inner Asia into counties like those around Chang’an; it meant that many rulers of the old Türk world recognized Taizong’s superior rank, for as long as the power and relationships behind it lasted.

Ruling Through Chiefs

Victory raised a hard question: what to do with the more than 100,000 Eastern Türks who submitted? Officials debated settling them inside the frontier, sending them back beyond the Yellow River, or breaking them into small groups. Wei Zheng himself argued for sending them north; the court instead settled many in the Ordos, the region inside the great northern bend of the Yellow River. Thousands of Türk families lived in Chang’an, and many Türks served in Tang armies.

The key tool was the bridle prefecture (jimi zhou). A chief received a Chinese-style office such as prefect. He kept leading his own people, recognized the Tang emperor, and supplied troops when called; the image of a loose bridle suggests guidance without close control. As the historian Jonathan Skaff stresses, this worked partly because the Tang court and its steppe neighbors shared many political customs, such as oaths, marriage alliances, and gift exchange.

Bridle prefectures belonged to a wider frontier toolkit. The Tang could fight; it could negotiate through envoys, trade, gifts, hostages, titles, and marriages (in 641 the princess Wencheng was sent as a bride to Songtsen Gampo, ruler of the rising Tibetan Empire); and it could incorporate by resettling migrants, recruiting allied cavalry, and making chiefs into officials. Indirect rule extended Tang reach cheaply, but only while both sides gained from it.

Here we hear from the other side of the bridle. The monument honors the Türk prince Kül Tigin and was set up by a Türk empire that broke free of Tang control in the 680s; the “fifty years” are roughly 630 to 680. What looked from Chang’an like a successful system looks here like humiliation. The authors wanted to warn their people never again to abandon their own qaghan, so they made Tang rule sound as shameful as possible. That makes the passage an argument, not a falsehood, just like Taizong’s “three mirrors.” Cooperation is not the same as consent.

Westward: A Web, Not a Block

The same bridle logic stretched west. In 640 Tang forces conquered Gaochang, an oasis kingdom near Turfan, and made it a directly governed prefecture. Yanqi (Karashahr) was attacked in 644, and Kucha fell in 648 with the help of allied troops. Under Gaozong, Tang and allied armies defeated the Western Türk qaghan Ashina Helu in 657, and in 658 the Anxi (“Pacify the West”) Protectorate moved to Kucha. A protectorate was a military command that supervised distant kings and peoples rather than governing them directly. A map of the empire in 661 shows Tang territory reaching deeper into Central Asia than the Han had, but inside that line control varied and shifted with distance, supply, and the rise of Tibet.²

Place 6 · The Fortress: The Limit at Ansi

The sixth place is where the conqueror found his limit. Goguryeo was a powerful Korean kingdom stretching from northern Korea into southern Manchuria, with its capital near modern Pyongyang; it had already defeated the Sui. Its western frontier was Liaodong, the region east of the Liao River in modern northeast China, guarded by a chain of fortresses.

After a coup in Goguryeo in 642 and attacks on Silla, a Korean kingdom allied with the Tang, Taizong decided on war, against the advice of most of his ministers. He ordered preparations in 644. In the spring of 645 his armies crossed into Liaodong, captured about ten fortresses, and won field battles. Then the campaign stalled at Ansi. For about two months the Tang built a great earthen ramp toward the walls, and when part of it collapsed, the defenders seized it. Supply lines lengthened and winter approached. In October Taizong ordered a retreat.

This was no repeat of the Sui disaster at the Salsu River. The army withdrew in order; the official history reports small combat losses but heavy losses of horses, figures historians treat with caution. But Goguryeo was not broken. Ansi only had to last until winter.

In Sima Guang’s eleventh-century account, Taizong then ordered sacrifices for Wei Zheng and had the fallen memorial stone set up again. The mirror he had lost was the critic who might have saved him from this war. Later raids during his lifetime also failed.

Coda: Korea after Taizong, 649–676

Taizong died in 649. His son Gaozong tried a new approach: alliance. Tang and Silla forces destroyed Baekje, in southwestern Korea, in 660, and in 668 their combined armies captured Pyongyang and ended Goguryeo. What Taizong could not do alone, his son did with an ally.

Then the alliance broke. Tang officials tried to govern the conquered lands through military commands, including the Andong (“Pacify the East”) Protectorate at Pyongyang, but Silla had expected those lands for itself. From 670 to 676 the former allies fought. By 676 the Tang had pulled the Andong Protectorate back to Liaodong, and Silla held most of the peninsula south of the Taedong River. The allies had agreed on destroying their enemies, not on who would rule afterward.

Epilogue: Back at the Tomb

The story ends where it began, at Zhaoling. After Taizong died, Gaozong set up stone statues of fourteen foreign rulers at the tomb’s north gate, among them Türk qaghans, oasis kings, the Tibetan emperor, and the queen of Silla; archaeologists excavated fragments and inscribed bases in 2002–2003. If the six horses remembered the Saddle, these statues remembered the Steppe: Taizong as Heavenly Qaghan, ruler of many peoples.

They also exaggerated. Several of those rulers never came to Chang’an, and within twenty years Silla would be fighting the Tang. What the tomb left out matters just as much: the brothers killed at the Xuanwu Gate, the payment at the Bian Bridge, the retreat from Ansi, and the critic whose stone Taizong knocked down and raised again. A monument is an argument, like the Kül Tigin inscription and the “three mirrors.”

Closing Synthesis

The early Tang story can be remembered through five anchor dates. In 618, Li Yuan proclaimed the Tang, though reunification took until 628. In 626, Li Shimin seized the throne at the Xuanwu Gate and then bought off a Türk army at the Wei River. In 630, the Eastern Türks collapsed and Taizong became Heavenly Qaghan. In 645, his invasion of Goguryeo stalled at Ansi. In 668, Tang and Silla destroyed Goguryeo, and by 676 Silla had pushed the Tang out of most of Korea.

The dates mark turns in an argument about power. Early Tang strength rested on three linked things. Information came from registers, the law code, approved texts, and official histories. Resources included grain, cloth, labor, trained officials, fubing rotations, and allied cavalry. Relationships tied the ruler to critical advisers, local elites, steppe chiefs, and allied kingdoms. None worked alone: registers were useless if households fled, and titles worked only while chiefs found them worth keeping. Where cooperation held, in Wei Zheng’s court, in registered villages, and among Türk chiefs after 630, the Tang was strong. Where it failed, at Ansi, with Silla after 668, and with the Türks who broke away in the 680s, the most powerful army in East Asia could not hold what it had won.

Historians still debate what made the early Tang strong: its institutions, its ruler, or its allies. Traditional historians made Taizong the model emperor, partly because his own court shaped the histories. Bingham and Twitchett showed how the record was arranged for the winner; Howard Wechsler explained the Wei Zheng ideal as both a real practice and a political model; Skaff, David Graff, and Shao-yun Yang placed the frontier story in a shared world of alliances and crises. Each answer has limits. The institutions came mostly from the Sui, which still collapsed. Taizong kept critics close, but he also killed his brothers and overreached at Ansi. Allies broke the Türks and made 668 possible, but they had their own goals, as Silla proved. A strong answer picks one and explains how it depended on the other two.

The Sui built much of the machinery. The early Tang’s achievement was to run it without breaking the households that powered it, and to turn enemies into partners wherever it could. Swords won the Tang its empire; cooperation kept it. Where victory could not be turned into cooperation, Tang power stopped.

Notes

1. Tang official history was built in layers. Court diarists recorded the emperor’s words and acts day by day; historians compiled those notes into “Veritable Records,” year-by-year accounts of each reign; and later scholars drew on the Veritable Records to write dynastic histories such as the Old Book of Tang. By tradition, an emperor did not read the records of his own reign, so that historians could write without fear. According to the Tang historical record, Taizong pressed his ministers to let him see them anyway, and in 643 the draft Veritable Records of his father’s reign and his own were presented to him. He objected that the account of the Xuanwu Gate was too vague and ordered it written plainly, as a righteous act that had saved the state. Denis Twitchett’s The Writing of Official History under the T’ang traces how such pressure shaped the record. The result is a founding story in which Li Shimin plans the rising of 617, wins the wars almost single-handedly, and strikes at his brothers only to save the dynasty, while Gaozu appears hesitant and Li Jiancheng unworthy. None of this means the coup did not happen or that Li Shimin was not a gifted general. It means separating what the sources agree happened (an ambush, two brothers and ten nephews killed, an abdication) from the explanation the winner wanted readers to accept. ↩

2. Empire maps need to be read with suspicion. A widely reproduced modern outline map of the Tang in 661 shades the core of direct rule darkly and the western protectorates more lightly, already a warning that control was not equal everywhere. An older map in Albert Herrmann’s Historical and Commercial Atlas of China (1935) draws a single boundary for about 700, half a century after Taizong’s death, when the Western Türks had been defeated and Tibet had become a major rival; its spellings and some interpretations reflect 1930s scholarship. A single line hides several kinds of authority: ordinary prefectures where the court collected taxes and appointed officials, military protectorates, oasis kingdoms with their own kings, and steppe communities led by chiefs holding Tang titles. Some accepted Tang titles when the empire was strong and dropped them when Tibet or a revived Türk empire offered better terms. Before treating any shaded area as ordinary Tang territory, ask who collected the taxes, who appointed the officials, and who commanded the soldiers there. ↩

Suggested Reading for Deeper Preparation

Denis Twitchett, ed., The Cambridge History of China, vol. 3, Sui and T’ang China, 589–906, Part I (1979). The fullest English account of the founding, Taizong’s reign, early Tang institutions, and the Korean wars. The standard reference for dates and administrative detail.

Howard J. Wechsler, Mirror to the Son of Heaven: Wei Cheng at the Court of T’ang T’ai-tsung (1974). A study of Wei Zheng and remonstrance. Essential for the “three mirrors” and for why Taizong’s court became a lasting model of good government, and what that model left out.

Denis Twitchett, The Writing of Official History under the T’ang (1992). How court diaries, Veritable Records, and dynastic histories were compiled, and how emperors, Taizong included, could shape them. The key book for reading the 626 coup critically.

Woodbridge Bingham, The Founding of the T’ang Dynasty: The Fall of Sui and Rise of T’ang (1941). An early, still-cited argument that the official histories inflated Li Shimin’s role and minimized Li Yuan’s.

David A. Graff, Medieval Chinese Warfare, 300–900 (2002). Explains how Li Shimin won the civil wars, including Hulao in 621, and why Korea was so hard. His article “The Reach of the Military: Tang,” Journal of Chinese History 1 (2017), is the best short guide to the fubing system.

Jonathan Karam Skaff, Sui-Tang China and Its Turko-Mongol Neighbors: Culture, Power, and Connections, 580–800 (2012). Treats Tang frontier relations as diplomacy within a shared Eurasian political culture. Best for the Heavenly Qaghan title, bridle prefectures, and the logic of alliance.

Shao-yun Yang, Early Tang China and the World, 618–750 CE (2026). A new synthesis of early Tang foreign relations that reads the victory of 630 and the Heavenly Qaghan title through steppe politics as well as court politics.

Wallace Johnson, trans., The T’ang Code, 2 vols. (1979–1997). The English translation of the code and its 653 commentary; a few articles show how law expressed family and status hierarchy.

Mark Edward Lewis, China’s Cosmopolitan Empire: The Tang Dynasty (2009). A thematic synthesis of law, land, military service, and foreign relations that links this lecture to Chang’an and its elite in Lecture 3.