Emperor Xuanzong of Tang

A Tributary Horse for Emperor Xuanzong, painted in the 12th century during the subsequent Song dynasty

Emperor Xuanzong made his wife Crown Princess Wang empress. Meanwhile, Princess Taiping continued to be listening to politics with curtains in the court, highly extremely influential in governmental matters through Emperor Ruizong, the group of chancellors openly frequented her house and most chancellors, forbidden troops, officials and warlords were her associates. (Of the seven chancellors at the time, five – Dou Huaizhen, Xiao Zhizhong, Cen Xi, Cui Shi, and Lu Xiangxian – were made chancellors at her recommendation, although Lu was not considered a member of her party.) As a result, the war between her and him continued more seriously. Liu Youqiu and the general Zhang Wei (張暐), with Emperor Xuanzong's approval, planned to mobilize the imperial guards to kill several of those chancellors – Dou Huaizhen, Cui Shi and Cen Xi. However, after Zhang told the plan to the imperial censor Deng Guangbin (鄧光賓), the news was leaked. At the request of Princess Taiping's, Emperor Ruizong issued an order to arrested Liu, and initially set to be executed. But Emperor Xuanzong interceded on his behalf with Emperor Ruizong, and Liu, Zhang, and Deng were spared but exiled.[18]

Later in 712, in one of Princess Taiping's plans to oust him, at her request, Emperor Ruizong decreed that Emperor Xuanzong lead a group of soldiers to examine the northern border. However, the group of conscripted soldiers was disbanded in spring 713, and the plan was never carried out.[18]

By summer 713, it was said that Princess Taiping, Dou, Cen, Xiao, Cui; along with other officials Xue Ji, Li Jin (李晉) the Prince of Xinxing (a grandson of Li Deliang (李德良), a cousin of Tang's founder Emperor Gaozu), Li You (李猷), Jia Yingfu (賈膺福), Tang Jun (唐晙); the generals Chang Yuankai (常元楷), Li Ci (李慈), and Li Qin (李欽); and the monk Huifan, were plotting to overthrow Emperor Xuanzong. It was further said that they discussed, with the lady-in-waiting Lady Yuan, to poison the gastrodia elata that Emperor Xuanzong routinely took as an aphrodisiac. When this alleged plot was reported to Emperor Xuanzong by Wei Zhigu, Emperor Xuanzong, who had already received advice from Wang Ju (王琚), Zhang Shuo, and Cui Riyong to act first, did so. He convened a meeting with his brothers Li Longfan the Prince of Qi and Li Longye the Prince of Xue (who had changed their names to Li Fan and Li Ye by this point to observe naming taboo for Emperor Xuanzong), Guo Yuanzhen, along with a number of his associates – the general Wang Maozhong (王毛仲), the officials Jiang Jiao (姜皎) and Li Lingwen (李令問), his brother-in-law Wang Shouyi (王守一), the eunuch Gao Lishi, and the military officer Li Shoude (李守德) – and decided to act first. On 29 July,[19] Emperor Xuanzong had Wang Maozhong take 300 soldiers to the imperial guard camp to behead Chang and Li Ci. Then, Jia, Li You, Xiao, and Cen were arrested and executed as well. Dou fled into a canyon and committed suicide by hanging. Xue Ji was forced to commit suicide. When Emperor Ruizong heard about this, he quickly ascended the tower at Chengtian Gate (承天門) to ascertain what was happening. Guo reported to him Emperor Xuanzong's intentions, and Emperor Ruizong felt compelled to affirm Emperor Xuanzong's actions in an edict. The next day, on July 30, Emperor Ruizong issued an edict transferring all authorities to Emperor Xuanzong. Meanwhile, Princess Taiping, hearing what happened to her associates, fled into a temple in the mountains, only appearing three days later. Emperor Ruizong asked Emperor Xuanzong for her pardon, but he refused. Emperor Xuanzong ordered her to commit suicide at home, and put to death her sons and associates, except for Xue Chongjian. Princess Taiping's assets were confiscated, and it was said that there was so much treasure, livestock, and real estate that it took several years: more than thirty years for the accounting to be complete. Emperor Ruizong moved to a secondary palace, Baifu Hall (百福殿) and would remain there until his death in 716.[18][20]

Emperor Xuanzong's Kaiyuan era is usually viewed as one of the golden ages of Chinese history – a period of political stability, peace in society, and economic prosperity, in addition to advances in education, literature, music, painting, sculpture, and religion.[21]

Spring Outing of the Tang Court, by Xuanzong era artist Zhang Xuan, 8th century original

Meanwhile, Zhang Yue and Liu Youqiu served as chancellors, but they were soon displaced by Yao Yuanzhi (who then changed his name to Yao Chong) and Lu Huaishen. Changing the system of having a large group of chancellors simultaneous, as had been the case throughout Tang, Emperor Xuanzong reduced the numbers to two (or sometimes three) for the rest of his reign.[22] Yao was considered a highly capable administrator, and with him ruling on most important matters and Lu assisting, the government was said to be highly efficient.[20]

In 714, Emperor Xuanzong carried out a series of political reprisals against the cruel secret police officials of Wu Zetian's reign, exiling the ones that were still alive and eventually barring their descendants from holding political offices. At the urging of Jiang Jiao's brother Jiang Hui (姜誨), he also exiled a number of chancellors – Wei Sili, Wei Anshi, Zhao Yanzhao, and Li Jiao – from Emperor Zhongzong's reign whom Jiang accused of being unable to curb Empress Wei's abuse of power.[20]

Also in 714, Emperor Xuanzong, wanting to punish the Khitan and the Xi for having defeated Tang forces during Emperor Zhongzong's reign, commissioned the general Xue Ne to attack them, but Xue suffered another devastating loss to them, at the casualty rate of 80–90%. However, later in the year, when the Tibetan Empire attacked, Emperor Xuanzong again commissioned Xue to defend against the attack, and Xue was able to repel the Tibetan forces. Subsequently, though, although both sides tried to invoke the marriage between Li Shouli's daughter Princess Jincheng and Me Agtsom, emperor of the Tibetan Empire, in seeking peace, the two sides could not reach an agreement and remained in border conflict yearly. In response, Emperor Xuanzong established the office of jiedushi (military governor) of Longyou Circuit (隴右, headquartered in what is now Haidong, Qinghai), with a centralized command of 12 prefectures under a single military general.[20] Eventually, the establishment of jiedushi would be extended to other parts of the empire.[23]

Also in 714, Emperor Xuanzong created Li Siqian, his second son and the son of his then-favorite concubine Consort Zhao, crown prince. (Emperor Xuanzong's wife Empress Wang was sonless.)[20]

Meanwhile, the Tang relationship with Qapaghan Qaghan of the Göktürks had fluctuated during the first few years of the Kaiyuan era, as minor hostilities occurred at the borders as well as contests over vassals' loyalty for the two states, but they were also at times friendly to each other, with Qapaghan requesting at times to marry a Tang princess and Emperor Xuanzong agreeing to the proposal. In 716, however, Qapaghan was killed in battle against the Bayegu (拔野古), and from that point on, lacking his efficient leadership, the Göktürks, while remaining an important regional power, posed much less of a threat to China,[20] although at times still capable of dealing serious defeats to Tang forces, as was the case in 720 when the Göktürk general Tonyukuk defeated the Tang garrison at Liang Prefecture (涼州, roughly modern Wuwei, Gansu) and the Tang vassal Basmyl.[24] Meanwhile, Tang, the Tibetan Empire, and the Umayyad Caliphate were constantly engaging in a three-way tug of war for influence in the Xiyu (i.e., modern Xinjiang and former Soviet Central Asia) region. In 715, for example, when the king of Bahanna (拔汗那) was expelled by a new king supported by the Tibetan Empire and the Umayyad Caliphate, Tang forces commanded by the general Zhang Xiaosong (張孝嵩) attacked the new king and restored the old king.[20] General Tang Jiahui led the Chinese to defeat the following Arab-Tibetan attack in the Battle of Aksu (717).[25] The attack on Aksu was joined by Turgesh Khan Suluk.[26][27] Both Uch Turfan and Aksu were attacked by the Turgesh, Arab, and Tibetan force on 15 August 717. Qarluqs serving under Chinese command, under Arsila Xian, a Western Turkic Qaghan serving under the Chinese Assistant Grand Protector General Tang Jiahui defeated the attack. Al-Yashkuri, the Arab commander and his army fled to Tashkent after they were defeated.[28][29]

The Great Mosque of Xi'an, one of China's oldest mosques, built during the reign of Emperor Xuanzong.

In and around 716, there was a major locust infestation in the central China region. At Yao's suggestion, Emperor Xuanzong ordered an extensive campaign of extermination, which was said to reduce the impact of the infestation and ward off a major famine. Later in 716, however, due a corruption scandal involving Yao's sons and his associate Zhao Hui (趙誨), Yao incurred displeasure from Emperor Xuanzong and offered to resign. He and Yuan Qianyao, who replaced Lu after Lu's death earlier in 716, were removed from their offices and replaced with Song Jing and Su Ting, with Song making more of the important decisions and Su assisting. Yao would not return to the chancellorship, but would remain influential as a key advisor for Emperor Xuanzong until Yao's death in 721. Contrary to the practical and flexible Yao, Song was more interested in emphasizing integrity and rule of law in governance, and it was said that while Yao's and Song's emphases were different, they were both regarded as instrumental in establishing the rule of Kaiyuan and that subsequent chancellors could not compare to them.[20]

Meanwhile, Song and Su had carried out a stern campaign against the use of coins that were not officially forged by the government, which brought popular resentment that Emperor Xuanzong found problematic. In 720, he removed Song and Su from chancellor offices and replaced them with Yuan and Zhang Jiazhen, and in 721 added Zhang Yue as a chancellor as well.[24]

Meanwhile, by 722, Empress Wang, who had contributed to Emperor Xuanzong's reign by providing suggestions, had begun to lose favor to Consort Wu, a great-grandniece of Emperor Xuanzong's grandmother Wu Zetian. Emperor Xuanzong secretly discussed with Jiang Jiao the possibility of deposing her, but Jiang Jiao careless leaked the discussion. At the urging of Zhang Jiazhen, who was friendly with Empress Wang's brother Wang Shouyi (王守一), advocated that Jiang Jiao be punished and exiled, and Jiang died in exile.

Meanwhile, at Zhang Yue's suggestion, the Tang northern border defense forces, which had about 600,000 men at that time, was reduced by 200,000 men to allow the soldiers to return home. Further, seeing that the Tang conscription system, due to abuses against the soldiers at the time, was near a collapse, as the soldiers were forced into long tours of duty but their families were not exempt from taxes, thus causing great numbers of desertions, Zhang suggested a switch to a recruitment-based system where soldiers were paid salaries. This allowed, for a time, Tang's soldier supply to be replenished. (Some later historians condemned Zhang for the abolition of the conscription system, believing the abolition to be the root of Tang's later fracturing, but some others, such as the modern historian Bo Yang, argued that Zhang's actions not only were necessary to restore the supply of soldiers but saved many lives.[30])

Emperor Xuanzong giving audience to Zhang Guo, by Ren Renfa (1254–1327)

In 723, Zhang Jiazhen was demoted on account of a corruption scandal involving his brother Zhang Jiayou (張嘉祐). His position was filled by Wang Jun, who was soon himself demoted over suspicions, never proven, that he was plotting treason.[31] With Zhang Yue thus effectively being the senior chancellor, Zhang Yue promoted literary studies, which Emperor Xuanzong also favored. In 724, he also commissioned the chief imperial astronomer Nangong Shuo (南宮說) to carry out a major astronomical survey to observe the sun and the North Star at various points of the empire.[24]

Also in 724, it was discovered that Wang Shouyi had engaged sorcerers to make amulets for Empress Wang to wear, hoping that the use of magic would allow her to have a son. Empress Wang was deposed and reduced to commoner rank, while Wang Shouyi was exiled and subsequently ordered to commit suicide in exile. Empress Wang died later in the year, and it was said that the eunuchs and the ladies in waiting mourned her bitterly and Emperor Xuanzong much regretted his treatment of her.[24] Still, after Empress Wang's removal and death, Consort Wu became undisputed mistress of the palace and was treated inside the palace like an empress would be. Still, in 726, when Emperor Xuanzong considered creating her empress, he encountered oppositions from officials on two grounds – that her Wu clan was hated by the people and that as she had her own sons, the position of Li Siqian the Crown Prince (whose name had been changed to Li Hong by this point) would be threatened. As a result, Emperor Xuanzong never created her empress. But Consort Wu's was a chief favorite of the emperor and undisputed mistress of the palace until her death and had political power.[32]

In winter 725, Emperor Xuanzong, at Zhang Yue's urging, carried out a magnificent ceremony at Mount Tai to offer sacrifices to heaven and earth.[24]

In 726, Zhang Yue was accused of corruption by several officials that he had blocked the advances of – Cui Yinfu (崔隱甫), Yuwen Rong, and Li Linfu – and was found to have committed corruption. At the intercession of Gao Lishi, however, Zhang Yue was removed only from his chancellor post and permitted to maintain his title and a number of other posts. He was replaced by Li Yuanhong, and subsequently, Du Xian was also added as a chancellor.[32]

In 727, at the suggestion of the general Wang Junchuo (王君㚟), Emperor Xuanzong commissioned Wang Junchuo to attack the Tibetan Empire, and after a Tibetan incursion in late 726, Wang counterattacked and inflicted losses on Tibetan forces commanded by the general Xinuoluogonglu (悉諾邏恭祿). Later in the year, though, Xinuoluogonglu and another general, Zhulongmangbuzhi (燭龍莽布支) attacked and captured Wang's home prefecture Gua Prefecture (瓜州, roughly modern Jiuquan, Gansu), taking Wang's father Wang Shou (王壽) captive. As a result, Wang Junchuo did not dare to counterattack, and subsequently blamed the defeat on a number of tribal chiefs in the area and had them exiles. In response, Yaoluoge Hushu (藥羅葛護輸), the nephew of one of the chiefs so exiled, Yaoluoge Chengzong (藥羅葛承宗), ambushed Wang Junchuo and killed him, and while Yaoluoge Hushu was forced to flee thereafter, for several years Tang did not engage in any offensive campaigns in the region.[32]

Around the same time, Emperor Xuanzong began to build a residential complex in the palace for imperial clan members, known as the Mansion of the Ten Princes (十王院), to centralize their residence. Thereafter, imperial princes, including the crown prince, would rarely live outside the palace complex.[32]

In 728, Emperor Xuanzong added the general Xiao Song as a chancellor. Subsequently, in 729, with Yuan, even though he was senior chancellor, unable to curb the disputes between Li Yuanhong and Du, Emperor Xuanzong removed all three from chancellor positions, promoting Yuwen and Pei Guangting to be chancellors in their stead – in Yuwen's case, for his abilities to find ways to add to the imperial treasury by imposing special taxes and levies. Later in the year, though, Yuwen made false accusations against the general Li Hui (李褘) the Prince of Xin'an (Emperor Xuanzong's second cousin) and was exiled, and subsequently died in exile. Still, it was said that it was starting from Yuwen's times that Emperor Xuanzong began to pay attention on taxes to replenish the imperial treasury, which traditional historians viewed as the start of his inflicting financial burdens on the people. Further, with Pei in charge of the civil service system, it was said that due to Pei's strict adherence to seniority, the Tang civil service system began to lose its ability to find talented people to serve in offices.[32]

In 730, the Khitan general Ketugan (可突干) killed the king Li Shaogu (李邵固) and took over the reign of the Khitan and the Xi personally, forcing the king of the Xi, Li Lusu (李魯蘇) to flee to Tang for protection. Tang sent an army to attack the Khitan, but meanwhile made peace with the Tibetan Empire. Initially, the campaign against the Khitan did not succeed, but in 732, with Li Hui in command, Tang forces dealt Ketugan a serious defeat and causing many of Ketugan's subordinates to defect and submit to Tang, although Ketugan was not captured.

Xuanzong's Journey to Shu, in the manner of the mid 8th century Tang artist Li Zhaodao, an 11th-century Song dynasty remake

Meanwhile, Tang also began to have periodic conflicts with Balhae, and in 733 Emperor Xuanzong tried to commission Dae Mun-ye (大門藝), the brother of Balhae's King Mu, to attack Balhae, along with forces from Silla, but the attack was not successful.[32]

Also in 733, Pei Guangting died, and at the recommendation of Xiao Song, he was replaced with Han Xiu, but soon, Song and Han were in repeated conflicts, and late in 733, both were removed and replaced with Pei Yaoqing, who became known for improving the food distribution system, and Zhang Jiuling, known for his integrity.[32][33] In 734, Emperor Xuanzong added Li Linfu, a close associate of Consort Wu, as a chancellor as well.[33]

Around the new year 735, Ketuhan was killed in an internal Khitan power struggle, and Khitan became a vassal again, although it would not stay so permanently.[33]

By 736, Emperor Xuanzong was described as having been tired of important affairs of state and beginning to become wasteful and exuberant in his lifestyle. Zhang tried to curb his behavior but thus began to lose favor, while Li Linfu was gaining power due to his association with Consort Wu. Further, Zhang supported Li Hong (whose name had been changed to Li Ying by this point), while Li Linfu and Consort Wu supported her son Li Mao (李瑁) the Prince of Shou and tried to have Li Mao made crown prince. In 736, due to Li Linfu's machinations that made Emperor Xuanzong believed that Zhang and Pei Yaoqing were improperly engaging in factionalism, Zhang and Pei Yaoqing were removed and replaced by Niu Xianke, who closely followed Li Linfu's will, and thereafter, Li Linfu would dominate the imperial government almost to the end of Emperor Xuanzong's reign. Li Linfu did all he could to stay in power, and carried out many dirty tricks against actual or potential threats to his power. He also severely discouraged criticism, ending the relative freedom that officials had to make proposals to Emperor Xuanzong. This was often viewed by traditional historians as the turning point of Emperor Xuanzong's reign, which up to that point was considered a golden age in Chinese history, toward a path of degeneration. The Song dynasty historian Sima Guang, in his Zizhi Tongjian, for example, commented:[33]

Of the chancellors that the Emperor commissioned after he took the throne, Yao Chong emphasized flexibility, Song Jing emphasized the rule of law, Zhang Jiazhen emphasized administrative abilities, Zhang Shuo emphasized literary talent, Li Yuanhong and Du Xian emphasized frugality, and Han Xiu and Zhang Jiuling emphasized honesty. All of them had their different talents. After Zhang Jiuling was demoted, however, the officials were all concerned about keeping their positions, and honest words no longer had a place in government.

In 737, with Zhang no longer in the government to protect him, Li Ying was deposed and subsequently forced to commit suicide. However, with Consort Wu dying later in the year, Emperor Xuanzong did not immediately accept Li Linfu's proposal to have Li Mao made crown prince. Rather, he chose an older son, Li Yu the Prince of Zhong, in 738.

Emperor Xuanzong's Journey to Sichuan, a late Ming dynasty painting after Qiu Ying (1494–1552).

Historians said that Emperor Xuanzong forced tens of thousands of beautiful women to live in his palace to please him, more than many other Tang emperors.[34] And he did not allow many to be set free even when they were old.[35] As Emperor Xuanzong turned his attention to pleasure-seeking with his favorite concubine Yang Guifei and her family, he paid less and less attention to the running of his empire, and much of his power fell into the hands of the corrupt Li Linfu (who was succeeded by Lady Yang's dissolute cousin Yang Guozhong) and the eunuch Gao Lishi.

At the same time, 751 saw the loss of the Battle of Talas against the Abbasid Caliphate. As a consequence, the Tang dynasty temporarily lost some of its influence in Central Asia to the emerging Abbasid Caliphate, as several Tang tributaries turned to the Abbasids.

Meanwhile, the jiedushi (military governors), most of whom were non-Han took more and more regional power into their own hands. Some successful generals included Geshu Han, known for victories over the Tibetan Empire; Gao Xianzhi, who conquered city states of the Xiyu region, eventually battling the Abbasids at Talas; and An Lushan who defeated and once again vassalized the Khitan. Eventually, in 755, An Lushan started the Anshi Rebellion at Fanyang. The rebels quickly seized the eastern capital Luoyang, and then the imperial capital Chang'an six months later. Emperor Xuanzong fled to Sichuan during the war and abdicated the throne to Li Yu (whose name had been changed to Li Heng at that point) (as Emperor Suzong).

Meanwhile, at Li Linfu's encouragement, Emperor Xuanzong began to promote non-Han generals to command large border armies, believing Li Linfu's assertion that non-Han generals were more likely to be personally loyal to Emperor Xuanzong himself and would not have clan entanglements, even though Li Linfu's own personal motivation was to prevent Han officials from going through the border command route to become chancellors, thus threatening him.[36] Such generals who rose in ranks included An Lushan, An Sishun, Geshu Han, and Gao Xianzhi.[33][36] By 742, the main Tang forces were all concentrated on the border, at nine different military circuits and one special military district (Lingnan), as well as three special coast defense districts (Changle, Donglai, and Dongmou):[36]

Meanwhile, it was said that Emperor Xuanzong had paid less attention to increasing revenues after Yuwen Rong's fall, but by 742 he was again interested in doing so, and such officials as Wei Jian (韋堅, a brother-in-law of Li Yu, whose name was changed by this point to Li Heng), Wang Hong (王鉷), and Yang Shenjin (楊慎矜) became favored, and often, matters having to do with finances were stripped out of other officials' responsibilities and given to them as special commissions.[36]

Late in 742, Niu Xianke died and was replaced by Li Shizhi.[36]

In 744, Eastern Tujue, after a series of internal turmoil and rebellions from its vassals, finally collapsed. Its vassal Huige rose and became the dominant power of the region, but formally submitted to Tang as a vassal.[36]

Yang Yuhuan mounting a horse, by Qian Xuan (1235–1305)

Meanwhile, after Consort Wu's death, Emperor Xuanzong had been depressed. When he saw his son Prince of Shou Li Mao's wife (his daughter-in-law) Yang Yuhuan (Princess of Shou, by virtue of marriage), he was infatuated with her, and he had her become a Taoist nun and gave Li Mao the wife of the general Wei Zhaoxun (韋昭訓) as his new wife and princess. Meanwhile, he secretly took the nun, Yang, into the palace. She became his senior-ranking concubine (guifei), known as Yang Guifei, and soon became so powerful that officials were bribing her family members to get preferential treatment. She was referred to inside the palace as "the Lady" and treated like an empress (as was consort Wu until her death).[36] He abducted more than 40000 women in his palace.[37] Some were not set free even after they were over 60 years old.[38][39][40][41]

Meanwhile, Li Linfu was beginning to conflict with Li Shizhi and Wei Jian, who were allies. Li Linfu, who engaged a group of secret police officials to investigate and manufacture evidence against political enemies, was able to get Wei and Li Shizhi demoted and exiled in 746. (Li Shizhi was replaced by Chen Xilie, who gained favor from Emperor Xuanzong for his knowledge in Taoism and sorcery.) In 747, Li Linfu further carried out a campaign of terror against exiled officials, and among the officials executed were Wei, Li Yong (李邕) and Pei Dunfu (裴敦復). Li Shizhi and Wang Ju, who had been instrumental in Emperor Xuanzong's initial actions against Princess Taiping, committed suicide.[36]

Meanwhile, in 747, Emperor Xuanzong wanted to expand the government's talent pool, and so issued an edict ordering that the people who had unusual talents to come to Chang'an to be examined by himself. Li Linfu, fearing that these examinees might accuse him of improprieties when they get to meet the emperor, suggested that these examinees go through two levels of preliminary examinations – by the local governments, and then by the executive bureau. As a result, no one passed the first two levels of preliminary examinations, and Li Linfu subsequently submitted a note to Emperor Xuanzong congratulating him that no talent has been overlooked by the imperial administration.[36]

Tang territories and Tang provinces by 742.

Meanwhile, also as of 747, An Lushan had become greatly favored by Emperor Xuanzong due to his military achievements and his willingness to flatter Emperor Xuanzong, Consort Yang, and her family members. Further, Li Linfu, apprehensive about the general Wang Zhongsi, who at that time was in command of four circuits (Hexi, Longyou, Shuofang, and Hedong), deprecated Wang in favor of An Lushan. In 747, after Li Linfu implicated Wang in hindering a campaign against the Tibetan Empire and further accused Wang of plotting a coup to overthrow Emperor Xuanzong and replace him with Li Heng, Wang was arrested and demoted, escaping death only at the pleas of Geshu, who was Wang's deputy and who subsequently was given the commands of Hexi and Longyou. An Lushan, who had already been in command of Fanyang and Pinglu Circuits, was also given Hedong, and thereafter was in command of the most elite troops of the empire.[36] Meanwhile, the ethnically Goguryeo general Gao Xianzhi had become prominent in the Xiyu region, expanding Tang power to the west.[42]

By 748, Consort Yang's cousins Yang Guozhong, Yang Xian (楊銛) and Yang Qi (楊錡), as well as her three sisters (who were created the Ladies of Han, Guo, and Qin), had become exceedingly wealthy and powerful due to the favors that Emperor Xuanzong showed them. It was said that their wealth topped all households in Chang'an. It was also said that by 749, the empire was so wealthy that Emperor Xuanzong viewed treasures as expendable and so awarded them without limit.[42]

Meanwhile, Li Linfu had a tight grip on power and favors from Emperor Xuanzong throughout the years, but as of 750, Yang Guozhong and Chen Xilie had allied with each other and were finding ways to eliminate Li Linfu's allies from government.[42]

As of 751, Tang was also facing defeats on two different external fronts – as Nanzhao's king Geluofeng (閤羅鳳), angry about unreasonable demands that the Zhang Qiantuo (張虔陀) the governor of Yunnan Commandery (雲南, roughly modern Chuxiong Yi Autonomous Prefecture, Yunnan) and Zhang's subsequent false accusations that he was planning to rebel, rebelled for real, and attacked and occupied Yunnan Commandery. A major attack by the general Xianyu Zhongtong (鮮于仲通) against Nanzhao failed terribly in 751, and subsequent defeats by Tang forces eventually led to a total of some 200,000 casualties among Tang troops. On the western front, Gao Xianzhi suffered a major defeat at the Abbasid forces at the Battle of Talas in 751 as well, ending the Tang expansion to the west.[42]

In 752, Wang Hong's brother Wang Han (王銲) was accused of treason after his associates rose in a failed coup at Chang'an. In the aftermaths, Wang Hong was forced to commit suicide, and Yang Guozhong, Chen, and Geshu Han further tried to implicate Li Linfu in the plot as well. After Li Linfu died in winter 752, Yang Guozhong succeeded him, and almost immediately accused Li Linfu of having been complicit in the rebellion of another general, Li Xianzhong (李獻忠). Li Linfu was posthumously disgraced, and his family was exiled.[42]

A rivalry soon developed between Yang Guozhong and An Lushan, and Yang Guozhong began to repeatedly warn Emperor Xuanzong that An was plotting rebellion. Emperor Xuanzong ignored the warnings. In 754, Yang Guozhong suggested that if An were summoned to the capital, he would surely refuse, and Emperor Xuanzong decided to try An – and An arrived in Chang'an immediately after being summoned. After this incident, Emperor Xuanzong no longer believed that An was plotting rebellion. Nevertheless, because of Yang Guozhong's opposition, he did not make An chancellor, as he was planning. Also in 754, with Yang Guozhong also trying to squeeze Chen out of the government, Chen resigned and was replaced by Wei Jiansu.[43]

Xuanzong with Consort Yang on a terrace with their attendants, by Japanese artist Kanō Eitoku (1543–1590)

In 755, Yang Guozhong further provoked An, who was then back at his post in Fanyang, by surrounding An's mansion at Chang'an and arresting and executing An's staff members. An, in fear and anger, rebelled in winter 755, and quickly reached and captured Luoyang after defeating Feng Changqing's undersupplied army. Subsequently, Emperor Xuanzong, believing in reports from the eunuch Bian Lingcheng (邊令誠) that Feng was cowardly and that Feng's superior Gao Xianzhi was corrupt, executed both Feng and Gao and replaced Gao with Geshu in defending Tong Pass from An's advances. An declared himself emperor of a new state of Yan at Luoyang, but with Geshu defending Tong Pass, An's advances stalled, while Tang forces commanded by Li Guangbi and Guo Ziyi made advances against An-controlled territory north of the Yellow River.[43] Meanwhile, though, Yang Guozhong, fearing that Geshu had designs against him, convinced Emperor Xuanzong to order Geshu to attack despite Geshu's warnings that doing so was risky. Geshu was subsequently defeated by An's forward commander Cui Qianyou (崔乾祐), and Tong Pass fell. With An's forces advancing on Chang'an, on 14 July 756,[44] Emperor Xuanzong, with Yang Guozhong suggesting that they flee to Jiannan Circuit, abandoned Chang'an and fled with Gao Lishi, Yang Guozhong, Wei, Li Heng, Consort Yang, and her family. The following day, 15 July, the imperial guards accompanying the emperor, angry at Yang Guozhong, rose and killed him and forced Emperor Xuanzong to kill Consort Yang as well. Subsequently, Emperor Xuanzong continued on to Jiannan, but Li Heng did not, but rather went to Lingwu, where, on 12 August,[4] Li Heng was declared emperor (as Emperor Suzong). Meanwhile, without knowledge that Emperor Suzong had claimed the throne, Emperor Xuanzong, while still on his way to Chengdu, the capital of Jiannan Circuit, issued an edict that gave several of his sons various responsibility areas, under Li Heng's command overall; until this edict was issued, most of the realm only knew that Chang'an had fallen and had not known where Emperor Xuanzong had fled. When the news of Emperor Suzong's ascension reached Emperor Xuanzong at Chengdu on 10 September,[45] he recognized Emperor Suzong as the new emperor, and thereafter took the title of Taishang Huang (retired emperor) – although his edict recognizing Emperor Suzong appeared to still indicate desire to retain control like his father Emperor Ruizong did early in his reign:[46]

From now on, my edicts (敕, chi) shall be referred to as gao (誥), and submissions to me shall address me as Taishang Huang. All matters relating to the military or the state throughout the realm shall first be submitted to the Emperor before being submitted to me. After the capital is recaptured, I will no longer oversee the affairs of state.

However, perhaps to avoid the impression that he was keeping a rival government to Emperor Suzong, he sent the several chancellors that he had retained or created while on the journey to or after he arrived in Chengdu – Wei, Fang Guan, and Cui Huan – to Lingwu to formally invest imperial power on Emperor Suzong and to serve under Emperor Suzong.[46]