After the death of his father in 604, generally considered, though unproven, by most traditional historians to be a murder ordered by Yang Guang, he ascended the Sui throne.

Emperor Yang, ruling from 604 to 618, committed to several large construction projects, most notably the completion of the Grand Canal, and the reconstruction of the Great Wall.

With northern China in turmoil, Emperor Yang spent his last days in Jiangdu (江都, in modern Yangzhou, Jiangsu), where he was eventually strangled in a coup led by his general Yuwen Huaji.

Despite his accomplishments, Emperor Yang is generally considered by traditional historians to be one of the worst tyrants in Chinese history and the reason for the Sui dynasty's relatively short rule.

In 582, Emperor Wen set up a branch of the executive bureau of his government (尚書省, Shangshu Sheng) at Bing Province and made Yang Guang its head.

In 588, Emperor Wen moved Yang Guang's headquarters to Shouchun (壽春, in modern Lu'an, Anhui), and made him the commandant there as well as the head the branch of the executive bureau established there.

In spring 589, the generals Han Qinhu (韓擒虎) and Heruo Bi (賀若弼), both under Yang Guang, crossed the Yangtze River and approached the Chen capital Jiankang.

Such commonly believed tales include the following: By 602, his brother, Yang Xiu the Prince of Shu, who, was commandant of Yi Province (roughly modern Chengdu, Sichuan), and had great resources at his disposal.

He ordered that major construction projects be carried out at Luoyang, commensurate with the necessities of having it as the actual capital, and he left his oldest son, Yang Zhao the Prince of Jin, in charge of Chang'an.

He conscripted several hundred thousands of young men to dig a lengthy trench to surround the Luoyang region, intending that it serve as a defense perimeter.

He then personally visited the imperial tent of Ashina Rangan, whose display of submission and loyalty caused Emperor Yang to bestow much honor and wealth on him.

In spring 608, Emperor Yang conscripted over a million men to construct the Yongji Canal (永濟渠), from the Yellow River to Zhuo Commandery (涿郡, roughly modern Beijing).

Later in spring 609, Emperor Yang conducted a tour of the newly conquered Tuyuhun territory, and sent several generals to chase down Murong Fuyun.

In response to the conscription order, even more men deserted and joined the agrarian rebels, throwing the northern central part of the empire into a state of confusion.

Emperor Yang, in fear, lifted the siege on Liaodong and also ordered the southern offensive to be terminated, returning to Zhuo Commandery while sending Yuwen and Qutu Tong (屈突通) south to aid Luoyang.

While generals such as Zhang Xutuo and Wang Sichong enjoyed victories here and there, the situation was deteriorating for the welfare of the Sui state at large.

In accordance with Turkish customs, Princess Yicheng had married him as her husband's successor; having been well treated by the empress during an earlier visit, though, she sent a secret warning of his plans to the emperor and his wife.

The imperial train sought refuge at the commandery seat in present-day Daixian, Shanxi,[5] which Shibi Khan and his army put under siege on 11 September.

Yuwen Shu suggested that Emperor Yang take the most elite guards and try to fight out of the siege, but Su Wei and Fan Zigai opposed this.

Meanwhile, at Yu Shiji's advice, Emperor Yang also personally visited the soldiers defending the city, raising morale by promising to end the campaigns against Goguryeo and to reward them with honors and treasure.

With the danger passed and credit muddled, Emperor Yang followed the advice of Su and Yuwen to renege on most of his promises: he did not return to the capital Chang'an, but went to Luoyang instead; he continued to prepare a campaign against Goguryeo; he did not bestow any monetary rewards on the garrison or its reinforcements; and he was sparing in the promotion of the officers involved.

Empress Xiao, surprised and distressed by his comment, asked him why he was saying so, and he responded and smiled, "Honor and wealth and poverty and dishonor, as well as pain and pleasure, all come in cycles.

Meanwhile, not wanting to return to the turbulent north, he discussed with his officials about moving the capital to Danyang (丹楊, in modern Nanjing, Jiangsu).

Their commanders Sima Dekan (司馬德勘), Yuan Li (元禮), and Pei Qiantong (裴虔通), worried that Emperor Yang would punish them, began considering rebelling and taking the Xiaoguo Army north themselves instead.

It was not until Yuwen Huaji left Jiangdu that the Sui official Chen Leng (陳稜) buried Emperor Yang with reduced ceremony.

When Yang Su heard this, he reported to the Crown Prince, and thereafter an edict of the Emperor was forged to arrest Liu and Yuan and detain them at the jail at the Supreme Court.

That night, the Crown Prince ordered Consort Chen to have sexual relations with him.More detailed versions of the story largely alleged that Zhang Heng personally killed Emperor Wen by pounding his chest and breaking his ribs.

No coffin or human remains have been found in the tomb, but a number of artefacts have been recovered, including a pair of lion-shaped gold-inlaid iron door-knockers and a jade belt with gold decoration.

He was, in fact, quite a gifted artist himself, but one prone to horrible fits of jealousy and stubbornness, who seldom listened to the advice of more talented individuals.

[15] Emperor Yang of Sui is portrayed by Hong Kong actor Lawrence Ng in TVB's 1987 series The Grand Canal (大運河)