Emperor Suzong of Tang - As Crown Prince

As Crown Prince

As Li Heng's ascension to be crown prince was against Li Linfu's wishes, and also because Wei Jian, who drew favor from Emperor Xuanzong due to his abilities to increase revenues for the imperial treasury, was becoming a rival to Li Linfu at court, Li Linfu looked for ways to incriminate both Wei and Li Heng. In 746, when the official Yang Shenjin (楊慎矜), at Li Linfu's instigation, reported to Emperor Xuanzong that, one night, Li Heng met Wei while both were sightseeing, and shortly after, Wei met a friend of his, the general Huangfu Weiming (皇甫惟明) at a Taoist temple, Li Linfu used these incidents to accuse Wei and Huangfu of secretly pledging allegiance to Li Heng and planning to remove Emperor Xuanzong to replace him with Li Heng. Wei and Huangfu were arrested and interrogated by Yang, Wang Hong (王鉷), and Ji Wen (吉溫), but Emperor Xuanzong, who did not want the case to further explode into a major incident although he believed Li Linfu's accusations, demoted Wei and Huangfu out of the capital and, for the time being, stopped the investigation. However, when Wei Jian's brothers Wei Lan (韋蘭) and Wei Zhi (韋芝) submitted a defense of their brother Wei Jian later in 746—and the defense cited words from Li Heng—Emperor Xuanzong was incensed. Li Heng, in fear, divorced Crown Princess Wei and asked for the Wei brothers to be punished. The Wei brothers, along with a number of their associates—including the former chancellor Li Shizhi, Wei Bin (韋斌), Wei Jian's nephew Li Quan (李琄) the Prince of Xue, Pei Kuan (裴寬), and Li Qiwu (李齊物), were all demoted. (In 747, at Li Linfu's instigation, the Wei brothers, Huangfu, and Li Shizhi were all forced to commit suicide.)

Later in 746, yet another incident again nearly brought disaster to Li Heng. One of Li Heng's other consorts, Consort Du, was a daughter of the official Du Youlin (杜有鄰). Consort Du's brother-in-law Liu Ji (柳勣) had a dispute with the Du family and falsely accused them of using witchcraft in favor of Li Heng. Li Linfu had Ji Wen interrogate Liu, and Ji implicated Liu in the alleged plot as well. Du Youlin, Liu, and Liu's friend Wang Zeng (王曾) were all caned to death, and Li Heng felt compelled to expel Consort Du from the household as well. Li Linfu also used this case to have two other officials friendly with Liu, Li Yong (李邕) and Pei Dunfu (裴敦復), executed by caning.

In 747, when one of Emperor Xuanzong's favorite generals, An Lushan, visited the capital Chang'an to pay respect to Emperor Xuanzong, An, who was not Han, initially refused to bow to Li Heng—pretending that he was only loyal to Emperor Xuanzong and to no one else, including the crown prince, and that he did not even know what a crown prince was. Only after Emperor Xuanzong explained what a crown prince is—the reserve emperor, to succeed him later—was An willing to bow to Li Heng. This caused Emperor Xuanzong to favor An even more, but also later caused An to be apprehensive of whether Li Heng would bear continued resentment toward him over the incident.

Later in 747, Li Linfu tried to use yet another case to undermine Li Heng. The general Wang Zhongsi, who was raised with Li Heng inside the palace on account of the fact that his father Wang Haibin (王海賓) had died in battle in service to the empire, was accused of interfering with the campaign of another general, Dong Yan'guang (董延光), against Tufan. Li Linfu broadened the accusation to an accusation that Wang was planning to start a coup to overthrow Emperor Xuanzong and replace him with Li Heng. At the intercession of another general, Geshu Han, however, Wang was spared from death, and Li Heng was not implicated. It was said that during this time period, Li Linfu made other attempts to undermine Li Heng, but with Gao Lishi and Zhang Shuo's son Zhang Ji (張垍), who had married Li Heng's sister Princess Ningqing, protecting Li Heng, Li Heng escaped unharmed each time.

As of 754, the chancellor in power was Yang Guozhong (Li Linfu having died in 752), the cousin of Emperor Xuanzong's then-favorite concubine Consort Yang Yuhuan (unrelated to Li Heng's mother). Yang Guozhong and An were locked in a power struggle, and Yang repeatedly accused An of plotting a rebellion, but Emperor Xuanzong would not believe it, although Li Heng eventually came to agree with Yang Guozhong. In late 755, with Yang Guozhong repeatedly trying to provoke An into a rebellion, An finally did, from his base at Fanyang (范陽, in modern Beijing). After the rebellion started, Emperor Xuanzong briefly considered making Li Heng regent, but at the pleas of Consort Yang and her three sisters (who were fearful that Li Heng would act against them if he had regent powers), did not actually do so.

By summer 756, An had declared a new state of Yan as its emperor, and his forces were approaching Chang'an. on July 14, 756, Emperor Xuanzong, with Yang Guozhong suggesting that they flee to Jiannan Circuit (劍南, headquartered in modern Chengdu), abandoned Chang'an and fled with Gao Lishi, Yang Guozhong, Wei, Li Heng, Consort Yang, and her family. The following day, July 15, the imperial guards accompanying the emperor, angry at Yang Guozhong, rose at Mawei Station (馬嵬, in modern Baoji, Shaanxi) and killed him and forced Emperor Xuanzong to kill Consort Yang as well. Emperor Xuanzong then poised to continue to head toward Jiannan. The people in the Mawei region tried to persuade Emperor Xuanzong not to continue on—believing that Chang'an could be recaptured. Emperor Xuanzong asked Li Heng to try to comfort the people. Once Li Heng left Emperor Xuanzong's presence, however, Li Fuguo and Li Heng's sons Li Tan the Prince of Jianning and Li Chu the Prince of Guangping, persuaded Li Heng not to follow Emperor Xuanzong to Jiannan—arguing that with the physical barriers between Chang'an and Jiannan, that once they had left the region, Chang'an could no longer be captured. Li Heng agreed and had Li Chu report this to Emperor Xuanzong. Emperor Xuanzong agreed with Li Heng's decision, but he himself continued on to Jiannan. Li Heng, escorted by a small number of guard soldiers commanded by Li Tan, then headed to the border city of Lingwu. With the army at Lingwu pressuring him to take imperial title, Li Heng declared himself emperor on August 13 (as Emperor Suzong). When news of this reached Emperor Xuanzong in Jiannan, Emperor Xuanzong recognized Emperor Suzong as emperor and took the title of Taishang Huang (retired emperor), although he continued to exercise some imperial authority—including, for example, issuing an edict that posthumously honored Emperor Suzong's mother Consort Yang as Empress Yuanxian. (Some historians, including the modern historian Bo Yang, believed that Emperor Xuanzong's continued issuance of edicts, while not on the surface conflicting with Emperor Suzong's authority, caused Emperor Suzong pressure to try to recapture Chang'an as quickly as possible to avoid any contention for the throne—either in the form of Emperor Xuanzong himself resuming imperial authority or in the form of another imperial prince rising to defeat Yan.)