Emperor Wen of Sui (; 21 July 541 – 13 August 604), personal name Yang Jian (), childhood name Naluoyan (那羅延), Xianbei name Puliuru Jian (), was the founding emperor of the Sui dynasty of China. As a Buddhist, he encouraged the spread of Buddhism through the state.
He is credited with reunifying China proper in 589, bringing an end to nearly three centuries of political fragmentation that began with the breakaway of the Cheng-Han and Han-Zhao regimes from the Western Jin in 304. His reign also saw the initiation of the Grand Canal, a major infrastructure project that would later facilitate the integration of northern and southern China.
As a Northern Zhou official, Yang Jian served with apparent distinction during the reigns of the Emperor Wu and Emperor Xuan. When the erratic Emperor Xuan died in 580, Yang, as his father-in-law, seized power as regent. After defeating 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 Emperor Wu of Liang).
Generally speaking, Emperor Wen's reign was a great period of prosperity, not seen since the Han dynasty. Economically, the nation 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 in the north, neighbored Tibetan tribes in the west, Goguryeo in the northeast, and Champa (Linyi) in the south. By the end of Emperor Wen's reign, the Göktürks had split into an eastern and a western khaganate, the eastern one being nominally submissive to Sui, as was Goguryeo. Champa was defeated and, while not conquered, did not remain a threat.
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 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.
In 555, on account of Yang Zhong's accomplishments, Yang Jian received several official ranks, including the title of the Duke of Chengji County (). In 557, Dugu Xin, impressed with Yang Jian, gave his daughter, Empress Dugu Qieluo, to Yang and made her his wife. He was 16, and she was 13. After Yuwen Tai's son Emperor Ming of Northern Zhou came to the throne later that year, Yang Jian was made the vice minister of internal affairs, and he was created the greater title of Duke of Daxing Commandery ().
During the reign of Emperor Ming's brother Emperor Wu, Yang Jian was further promoted in military authority. After Yang Zhong's death in 568, he inherited the title of Duke of Sui. In 573, Emperor Wu took Yang Jian's daughter Yang Lihua to be the wife and crown princess of his son Yuwen Yun the Crown Prince, and further honored Yang Jian.
Yang, as the regent, abolished the wastefulness and cruel policies of Emperor Xuan, and he himself demonstrated both hard work and frugality, which impressed the people. Yang Jian, concerned about the potential threat posed by General Yuchi Jiong, summoned him back to the capital. However, Yuchi refused, believing that Yang Jian might be attempting to usurp the throne. Yuchi then rose at Xiang Province against Yang. He was supported by the generals Sima Xiaonan (), the commandant at Xun Province (勛州, roughly modern Xiaogan, Hubei) and Wang Qian (), the commandant at Yi Province (roughly modern Chengdu, Sichuan). Within 68 days, general Wei Xiaokuan defeated Yuchi, who eventually committed suicide. Wang Qian was also defeated, and Sima fled to Chen. To prevent Yuchi's former headquarters at Yecheng from being used as a base of opposition, Yang Jian ordered the city to be demolished. Emperor Wen abolished Northern Zhou's governmental organization of six departments, instead establishing five main bureaus—executive bureau (Shangshu Sheng (), examination bureau (Menxia Sheng (), legislative bureau (Neishǐ Sheng (), Palace Library, and eunuch bureau (Neishì Sheng (內侍省—note different tone and character versus 'legislative bureau')), with two additional independent agencies, 11 other independent departments, and 12 military commands.
Yang Jian posthumously honored his father, Yang Zhong, and his mother, Lady Lü, as emperor and empress. He made his wife, Duchess Dugu, empress and their eldest son, Yang Yong, crown prince. His relationship with Empress Dugu was so close and intimate that it resembled that of an ordinary married couple, and it even reached a point where it was difficult to determine who first proposed government policies. For this reason, within the palace they were referred to as the “Two Sages” (二聖, èr shèng). He also granted imperial titles to his brothers and other sons. Initially, he created Emperor Jing of Northern Zhou the Duke of Jie but later ordered the execution of all grandsons of Yuwen Tai, including the Duke of Jie. He assigned most of the important governmental matters to his officials Gao Jiong, Yang Su, and Su Wei. He also sent his sons out to key provinces with broad powers. Additionally, he commissioned the official Pei Zheng to carry out a project aimed at simplifying the penal code and reducing the penalties of harsh laws, a reform that was later largely accepted by subsequent dynasties.