Emperor Wen of Sui (; 21 July 541 – 13 August 604), personal name Yang Jian (), Xianbei name Puliuru Jian (), alias Narayana () deriving from Buddhist terms, was the founder and the first emperor of the Chinese Sui dynasty. The Book of Sui records him as having withdrawn his favour from the Confucians, giving it to "the group advocating Xing-Ming and authoritarian government." As a Buddhist, he encouraged the spread of Buddhism through the state. He is regarded as one of the most important emperors in Chinese history, reunifying China proper in 589 after centuries of division since the independence of the Cheng-Han and Han-Zhao dynasties from the Western Jin dynasty in 304. During his reign, the construction of the Grand Canal began.
As a Northern Zhou official, Yang Jian served with apparent distinction during the reigns of the Emperor Wu of Northern Zhou and Emperor Xuan of Northern Zhou. When the erratic Emperor Xuan died in 580, Yang, as his father-in-law, seized power as regent. After defeating the general Yuchi Jiong, who resisted him, he seized the throne for himself, establishing the new Sui dynasty. Yang Jian was the first ethnic Han ruler to control the entirety of North China after the Xianbei people conquered the region from the Liu Song dynasty (not counting the brief reconquest by the Emperor Wu of Liang).
Generally speaking, Emperor Wen's reign was a great period of prosperity, not seen since the Han dynasty. Economically, the dynasty prospered. It was said that there was enough food stored for 50 years. The military was also powerful. At the beginning of his reign, Sui faced the threat of the Göktürks to the north, and neighbored Tibetan tribes to the west, Goguryeo in the northeast, and Champa (Linyi) threatening the south. By the end of Emperor Wen's reign, the Göktürks had split into an eastern and a western kaganate, the eastern one being nominally submissive to Sui, as was Goguryeo. Champa was defeated and, while not conquered, did not remain a threat.
Emperor Wen is also famous for having only two concubines. Although he might have had additional concubines not documented by traditional historians, this is the fewest for an adult Chinese emperor, surpassed only by the monogamous Emperor Fei of Western Wei and the Ming Hongzhi Emperor. Emperor Wen loved and respected his wife Empress Dugu deeply, and he might not have had sexual relations with his concubines until after her death in 602.
Early life
Yang Jian was a member of the northwestern Chinese military aristocracy which had arisen during the previous period of division, and he had served as a general under the Xianbei-led Northern Zhou. Yang Jian's family was the Yang clan of Hongnong (弘農楊氏), which had Han origins but had intermarried with the Xianbei for generations. Yang Jian's clan specifically claimed descent from the Han Dynasty general Yang Zhen. Yang Zhen's eighth-generation descendant Yang Xuan () served as a commandery governor for a Yan state (Former Yan or Later Yan) during the Sixteen Kingdoms Period, and his descendants subsequently served the Northern Wei Dynasty. Yang Jian emphasized Han Chinese cultural identity throughout his reign.
Yang Jian's father was Yang Zhong (), a follower of the late-Northern Wei general Yuwen Tai, who later became prominent in the politics of the Western Wei under Yuwen's regency. Yang Jian's mother was Lady Lü, who gave birth to him in a Buddhist temple in Pingyi (馮翊, in modern Weinan, Shaanxi). A Buddhist nun was impressed with Yang Jian's appearance, and raised him in his early years. Yang Jian attended the imperial college for the sons of the nobility and high officials. When he was 14 years old, he was appointed to serve in the military under Yuwen Tai.