Hsüan Tsung, Pinyin Xuan Zong (temple name), XuanzongWade-Giles romanization Hsüan-tsung, personal name (Wade–Giles romanizationxingming) Li Lung-chiLongji, posthumous name , or shih, Ming Huang, or Wu Huang (shi) Minghuang  ( born AD 685 , Lo-yang  Luoyang, China—died 762 )  sixth , Chang’an [now Xi’an, Shaanxi province] )  temple name (miaohao) of the seventh emperor of the T’ang Tang dynasty (618–907) of China, which during his reign (712–756) achieved its greatest prosperity and power.

Hsüan Tsung Li Longji was the third son of Jui Tsungthe Ruizong emperor, who was himself a son of the empress Wu Hou. Hsüan Tsung Wuhou. Li Longji was born during a period when actual power was entirely in the hands of Wu HouWuhou, although his father was nominal emperor. Enfeoffed as prince of Ch’u Chu in 687, Hsüan Tsung Li Longji was reenfeoffed as prince of Lin-tz’u Linzi in 693 after Empress Wu’s Wuhou’s usurpation of the throne under her own name in 690. Toward the end of her reign he was appointed to several ceremonial posts at court, which gave him influence over the Imperial imperial guards and palace armies.

In the course of the complicated succession struggles that followed the death of the Empress empress in 705, Hsüan Tsung’s Li Longji’s father, Jui Tsungthe Ruizong emperor, was restored to the throne in 710. As a result of Hsüan Tsung’s Li’s key role in this coup, he was appointed heir apparent.

In 712 the ineffectual Jui Tsung Ruizong abdicated in favour of Hsüan Tsung his son (who took the temple name Xuanzong), but, at the urging of his Ruizong’s ambitious sister (the princess T’ai-p’ingTaiping), he remained “Supreme Emperor,” a sort of regent with control over appointments to high offices, which were filled with the Princess’ princess’s supporters.

In 713 Hsüan Tsung the Xuanzong emperor won a brief power struggle between himself and the princess T’ai-p’ingTaiping; she committed suicide, Hsüan Tsung Xuanzong then assumed full authority as emperor, and his father retired into seclusion.

Hsüan Tsung’s Xuanzong’s reign began well. He carried out a sweeping reform of the bureaucracy, which had become vastly inflated by great numbers of nominal and supernumerary officials, many of whom had been appointed by patronage or by the open purchase of their posts. Under HsüanXuanzong, the purchase of office was restricted and the authority of the throne, the efficient functioning of the bureaucracy, and the finances of the state were largely restored. Moreover, the canal system, upon which the capital at Ch’ang-an Chang’an (now Xi’an) relied and which had fallen into decay while Empress Wu the Wuhou empress resided in Lo-yangLuoyang, was restored to action. Successful campaigns were waged against the Tibetans, the Turks, and the KhitanKhitans (Chinese: Qidan).

During this early stage of Hsüan Tsung’s the Xuanzong emperor’s reign, which lasted until about 721, he successfully maintained a balance of power and influence between the competing factions of the examination-recruited ministers who had served the Wuhou empress Wu, the members of the Imperial imperial clan, and the palace officials and members of the families of the imperial consorts.

But a period of wide-ranging reforms in administration began in 720, and the whole structure of central government was changed in such a way as to concentrate more and more authority in the hands of the chief ministers. At the same time there was a marked resurgence of the influence of the old aristocracy at court, and the period 721–737 was one of continuous political tension between the aristocrats and the examination-recruited professional bureaucrats. The aristocratic faction managed to increase its influence in the bureaucracy during the implementation of a series of sweeping financial reforms that were initially successful. The population was effectively reregistered, bringing vast numbers of taxpayers onto the rolls and a sharp increase in revenue; the coinage was improved, and the transportation system was reformed so effectively that the Emperor emperor no longer had to move the court between Ch’ang-an and Lo-yang Chang’an and Luoyang periodically to avoid famine. The empire’s revenues increased, enabling the Emperor emperor to establish along the northern frontiers an ever-growing permanent military establishment (by the end of his reign numbering some 600,000 men), without overburdening the population.

The political influence of the aristocracy’s financial experts grew even greater in the latter part of Hsüan Tsung’s Xuanzong’s reign, and after 737, Li Lin-fuLinfu, chief representative of the aristocratic interest, became virtual dictator and the aristocratic party was firmly entrenched in power. From about 740 onward the Emperor’s emperor’s actual control of affairs began to decline. The reforms, which theretofore had mostly been necessary for greater administrative efficiency, now tended more and more to destroy the balance of political power. The chief ministers formally acquired unprecedented power and prestige as heads of the government. The financial experts, too, devoted more and more of their attention to purely exploitative measures designed to pay for court extravagance and the Emperor’s emperor’s increasingly expensive personal needs.

Moreover, after 737, the vast regional commands established earlier in the reign to control the northern border now began had begun to develop widespread powers in other fields and to acquire territorial authority. By the late 740s some of these generals had grown immensely powerful and began to intervene in court politics. Most important of them was Li Lin-fu’s Linfu’s protégé An Lu-shanLushan, who controlled the northeast and had an army of 180,000 troops. The central government had no standing armies under its own command to rival the forces of these military governors.

Meanwhile Hsüan Tsung Xuanzong had withdrawn more and more. Always a great patron of the arts—he had founded Imperial imperial music academies to provide court musicians and had patronized poets, painters, and writers—he now became deeply involved in the study of TaoismDaoism, from whose founder the T’ang Tang royal house claimed to be descended.

He also began to suffer from family problems, chiefly because he had fallen under the influence of at least two of his many consorts. The first was Wu Hui-feiHuifei, who had great influence from the early 720s until her death in 737; she played a part in the rise of Li Lin-fu Linfu and eventually became involved in unsuccessful plots to make her own eldest son heir to the throne in place of one of the Imperial imperial princes. The eventual heir apparent, however, was another prince (the future Su TsungSuzong emperor), who was opposed to Li Lin-fuLinfu.

The Emperor emperor also came under the influence of another favourite, the consort Yang Kuei-feiGuifei. During the later years of his reign, Hsüan Tsung the Xuanzong emperor became completely infatuated with her and heaped honours on members of her family. One of these relatives, her cousin Yang Kuo-chungGuozhong, rose rapidly to rival even Li Lin-fu Linfu in power and, on the latter’s death in 752, replaced him as the dominant chief minister.

There had already been some tensions between Yang Kuo-chung Guozhong and An Lu-shanLushan. With the removal of his patron at court, and the increasing hostility of Yang Kuo-chungGuozhong, An Lu-shan Lushan began building up his provincial power base in readiness for armed confrontation. This began at the end of 755. An Lu-shan’s Lushan’s forces swiftly struck into the northeastern provinces, and, by the summer of 756, they were approaching the capital of Ch’ang-an. Hsüan TsungChang’an. Xuanzong, accompanied only by a few troops and a small group of relatives and courtiers, fled to take refuge in SzechwanSichuan province, the power base of the Yang clan. They had reached Ma-wei Mawei when the soldiers mutinied, killed Yang Kuo-chungGuozhong, and forced Hsüan Tsung Xuanzong to have Yang Kuei-fei Guifei killed.

Shortly afterward, the heir apparent, who had fled separately to Ling-wuLingwu, west of the capital, proclaimed himself emperor. Hsüan TsungXuanzong, who heard of this only some time after it had occurred, acquiesced and abdicated formally in his favour. He lived in retirement until his death in 762.

Although Hsüan Tsung’s Xuanzong’s reign ended in political disaster and personal tragedy, it was a period of internal stability, good government, and prosperity, an era of confidence during which real progress was made in every field. The sudden end of this period not only changed the political system completely but it was also a dramatic, traumatic experience for the men people of the time. In the next decade the confident pride of Hsüan Tsung’s Xuanzong’s age was replaced by self-questioning, by withdrawal from public affairs, and by a new spirit of social and political criticism.