Tang SuzongLi Heng's era was one of the most turbulent eras in the Tang Dynasty. This was not only because the Anshi Rebellion caused national unrest, but also because of the dual political chaos caused by the simultaneous existence of two emperors, Tang Suzong and Tang Xuanzong. In such a political environment, various political struggles occurred one after another, and many shocking unjust, false and wrongful convictions occurred. The most famous of the unjust, false and wrongful cases during the Suzong era of the Tang Dynasty was the death case of Li Tanci, King of Jianning. This case not only caused a huge shock both inside and outside the court, but also changed the direction of the history of the Tang Dynasty. Friends who are familiar with the history of the Tang Dynasty know that Li Tan was Li Heng's third son and one of the best sons. Li Heng did not care about the relationship between father and son, and issued an edict to kill Li Tan, which is really heartbreaking.

There are different opinions on the historical records of this incident. The mainstream historical opinions attribute the cause of the case to Li Heng being deceived by the powerful eunuchs Li Fuguo and Zhang Liangdi. In the end, in order to protect Li Yu who was still the king of Guangping at the time, the third son Li Tan was executed. This statement is supported by many historical materials, but careful analysis reveals that it is full of loopholes. The cause of this case was that Li Fuguo and Zhang Liangdi accused Li Tan of being disloyal. He wanted to compete with Guangping King Li Yu for the crown prince position, and even set up a conspiracy to assassinate Li Yu. Li Heng was furious after receiving the accusation, and soon issued an edict to kill Li Tan. However, looking at the entire process of the case, there are doubts about this matter. Especially Li Yu's reaction seems to be completely inconsistent with historical records.

This case involves Li Heng's two most outstanding sons, Li Yu, King of Guangping and Li Tan, King of Jianning. Li Yu is Li Heng's eldest son and is highly regarded by Li Heng. After the Anshi Rebellion, Li Heng launched the Maweipo Revolution on his way to escape from Chang'an with Emperor Xuanzong of the Tang Dynasty Li Longji . From then on, the father and son parted ways. Li Longji fled to Chengdu in central Sichuan for refuge, while Li Heng fled to Lingwu in the northwest and proclaimed himself emperor. He mobilized Guo Ziyi, Li Guangbi and other armies to prepare to quell the Anshi Rebellion and regain the lost capitals of Chang'an and Luoyang. During this process, Li Yu stayed by his father's side and gave his father a lot of support. Therefore, after the counter-rebellion army was formed, he was appointed as the Grand Marshal of the World's Soldiers and Horses. He was nominally the supreme commander of the counter-rebellion army. In fact, the army was directly commanded by Deputy Marshal Guo Ziyi.

Compared with his elder brother Li Yu, Li Tan's performance when Li Heng fled Chang'an was not bad at all, and even worse. Before the Maweipo Incident, many of Li Heng's subordinates persuaded him to launch a coup, but Li Heng was always hesitant. As his son, Li Tan first stood up and advised Li Heng to make a decisive decision, and carefully analyzed the situation at the time and the pros and cons of the coup. Under Li Tan's persuasion, Li Hengcai made up his mind to launch a coup, killed the traitor Yang Guozhong, and forced Li Longji to execute Yang Guifei. On Li Heng's way to Lingwu, Li Tan took the lead and led the escort to clear the way, breaking through the rebel encirclement along the way, allowing Li Heng to reach Lingwu smoothly. It can be said that Li Tan's performance along the way, especially his decisive killing, made the first contribution to Li Heng's ascension to the throne in Lingwu.

When Lingwu formed a counter-rebellion army, choosing the general of the world's soldiers and horses became the most controversial topic. According to the unspoken political rules of the Tang Dynasty, the prince can only serve as the general marshal of the world's troops, and this position has become a pre-position of the prince since Li Longji ascended the throne. In other words, which prince is chosen to be the general marshal of the world's military forces shows that Li Heng intends to make him the crown prince. At that time, the brothers Li Yu and Li Tan were the most controversial ones in the court, and Li Heng also considered them as candidates for courtiers to discuss. In the end, Li Heng listened to the minister's persuasion and made Li Yu the marshal of the world's soldiers and horses, and Li Tan served as the guard of the Dianqin army around him. Judging from these historical records, Li Heng valued both brothers Li Yu and Li Tan equally, and their abilities were equally excellent.

Not long after Li Yu led his troops to suppress the rebellion, Li Tan, who stayed with Li Heng, had conflicts with Li Fuguo and Zhang Liangdi. He repeatedly complained to Li Heng about their illegal activities.Zhang Liangdi was Li Heng's favorite concubine at the time, and Li Fuguo was Li Heng's most trusted eunuch. The two teamed up to control the government and created a mess in the court. They were very afraid of Li Tan, so they framed Li Tan in front of Li Heng, saying that he was unwilling to lose the marshal of the world's soldiers and horses, and wanted to murder Li Yu and seize the throne of the crown prince. After this incident, Li Yu was furious and quickly issued an edict to kill Li Tan. This statement in the history books seems reasonable, but people who are familiar with the Tang Dynasty system will know at a glance that there are too many tricks in it, and there are many unknown secrets hidden in it.

First of all, the process of Li Heng's execution of Li Tan was too fast, without any investigation and trial by the court. Li Tan is not an ordinary clan member, but King Jianning, and is the Dianqin army responsible for the emperor's bodyguard. His case needed to be heard by the court system, but there is no record of this in the history books. Even if Li Tan really had some conspiracy, he should be allowed to self-identify instead of being executed without any notice. Moreover, Li Tan was Li Heng's third son and had made great contributions in the Maweipo Incident and his ascension to the throne. In any case, he should not make such a hasty decision. Even if Li Tan was really at fault, Li Heng could have been given a lighter sentence instead of executing his best son so ruthlessly. This simply lacked the human touch of father-son love.

Secondly, Li Fuguo and Zhang Liangdi said that Li Tan wanted to murder Li Yu and seize the crown prince's position because he was dissatisfied with Li Yu as the general of the army. But judging from Li Yu's reaction, it seems that this is not the case at all. If what Li Fuguo and Zhang Liangdi said is true, then Li Yu should hate Li Tan to the core. But instead of showing hatred for Li Tan, Li Yu hated Li Fuguo and Zhang Liangdi very much. He even wanted to return to the army to avenge Li Tan, but he finally gave in under the persuasion of the famous official Li Mi. However, the relationship between Li Yu and Li Heng turned cold afterwards. Although Li Yu was established as the crown prince, he was jealous of Li Heng. If it weren't for Li Mi's mediation, it would be difficult for Li Yu to retain his position as crown prince.

Thirdly, Li Heng and Li Yu’s father and son had completely different attitudes towards Li Tan’s death, and the contrast was huge. Although Li Mi persuaded Li Heng many times, Li Heng ostensibly expressed regret for Li Tan's death, but he did not take any substantive action. He was just putting on a show in the court, completely lacking the love of a father. And Li Yu was really sad about Li Tan's death, and even considered it the biggest regret in his life. After Li Yu ascended the throne, he not only posthumously named Li Tan Emperor Chengtian, but also built him Shunling, an emperor-level mausoleum, making him a rare royal prince in the Tang Dynasty who was posthumously named emperor without ever being a prince. Considering that Li Tan was unmarried when he died, Li Yu also issued an edict that the fourteenth daughter of his aunt Princess Xingxin, who died in infancy, be given to him for a secret marriage, and she was posthumously named "Queen of Obedience".

Judging from Li Yu's behavior towards Li Tan, the two of them are not like competitors for the position of crown prince at all, but more like real brothers. You must know that when Li Yu ascended the throne, there was a struggle for the throne. Li Fuguo led his army to kill Li Xi, the Yue king supported by Zhang Liangdi, but Li Yu showed no brotherhood at all. Li Xi is also Li Heng's second son, Li Tan's brother, and one of Li Yu's brothers. It can be seen from Li Yu's different attitudes towards Li Tan and Li Xi that Li Xi is Li Yu's enemy, while Li Tan is Li Yu's most valued brother. Therefore, this fact proves that Li Tan's statement that he was dissatisfied with Li Yu as the general of the army is completely non-existent, and that he wanted to murder Li Yu was also a lie made up by Li Fuguo and Zhang Liangdi.

In fact, such lies cannot withstand investigation at all. Li Heng only needs to send someone to do a little investigation to know the truth of the matter. But Li Heng seemed unwilling to even conduct an investigation and rushed to issue an edict to execute Li Tan. This was not the behavior of a father. Even if Li Tan's contributions to the Maweipo Incident and Lingwu's support were not taken into account, the two of them had a father-son relationship that was related by blood. How could they be so ruthless? This incident also caused a huge shock in the court. In addition to the disappointment of Crown Prince Li Yu and his party to Li Heng, the departure of the famous minister Li Mi was Li Heng's biggest loss.Without the assistance of Li Mi, the "Zhuge of the Mid-Tang Dynasty", Li Heng's governance in the second half of the period was a complete mess. The Tang Dynasty also fell into endless internal strife, and the Anshi Rebellion dragged on for a long time.

Then the question arises. Since the reasons recorded in the history books are not valid, what is the real reason why Li Heng executed Li Tan? To answer this question, we have to start with the political background of the Tang Dynasty at that time. Tang Suzong Li Heng came to the throne during the Anshi Rebellion. He faced a series of difficulties from the moment he ascended the throne, and the throne was very unstable. Externally, the Tang Dynasty faced the devastation of the Anshi Rebellion. The two capitals of Chang'an and Luoyang were lost, and the country was in precarious turmoil. There was still unrest within the imperial court, because two emperors, Li Heng and Li Longji, were in power at the same time, and the strange phenomenon of dual politics appeared in the Tang Dynasty. Although Li Longji was far away in Chengdu as the Supreme Emperor, he already had many close ministers in the court, and they had a great negative impact on Li Heng's governance.

Faced with the dilemma of internal and external troubles, Li Heng chose to rely on the eunuch group to govern the country, so he reused eunuchs represented by Li Fuguo, Cheng Yuanzhen, and Yu Chaoen. However, Li Tan, who was the general of Li Heng's bodyguard, did not take this seriously. He impeached these eunuchs many times for abusing their power, and therefore had a very bad relationship with the eunuch group. On the contrary, Li Tan had a very good relationship with the princelings of Li Yu's group, and also had close contacts with Li Heng's chief adviser Li Mi. Li Tan spoke for the crown prince many times in court, which was one of the reasons why Li Yu later pursued Li Tan aggressively. The conflict between Li Tan and the eunuch group was essentially a conflict between him and Li Heng's philosophy of governing the country. Li Tan opposed the eunuch group, which made Li Heng feel very uneasy, and thus he became suspicious.

Li Tan was Li Heng's general of the bodyguard, but he had close contacts with Li Yu, who led the rebels, and spoke for him many times, which made Li Heng worried. The conflict between Li Tan and Li Fuguo and others made Li Heng worry that Li Tan would take unconventional measures when he had conflicts with the eunuch group. After all, Li Tan resolutely led the coup in the Maweipo Incident, and also insisted on the execution of Yang Guozhong and Yang Yuhuan. If Li Tan embarks on this path again when conflicts intensify, Li Heng is likely to lose his position as the second emperor. If this happens, Li Tan can either support Li Yu who is fighting abroad or restore Li Longji who has taken refuge in Chengdu. Judging from the political situation at the time, Li Tan's continued control of the palace guards was a huge threat to Li Heng.

It can be said that what induced Li Heng to have a murderous intention to kill Li Tan was the dark history of the Maweipo Incident, and the main reason was the choice made in the political context of internal and external troubles at that time. If he just deprives Li Tan of his military power, Li Heng is worried that Li Tan will join Li Yu, which will become a huge trouble. Moreover, Li Heng himself was very suspicious of Li Yu who was leading troops outside, otherwise he would not have let Yu Chaoen serve as the supervisor of the army. Under the political background of the time, Li Heng did everything he could to keep his position as emperor. Judging from historical records, he has completely lost the relationship between father and son. Not only did he kill Li Tan, but he also allowed Li Fuguo and Zhang Liangdi to continuously suppress Li Longji and his old officials in order to maintain his dominance.

However, Li Heng's series of operations did not bring him good results, and he eventually became the first emperor in the Tang Dynasty to be negatively evaluated. He had no achievements in his life, and the incident of Maweipo became a stain on his life. It was his son Li Yu who regained and the two capitals during the Anshi Rebellion. The Anshi Rebellion dragged on for a long time because he did not listen to Li Mi's correct advice. The emperors before Li Heng all had meritorious deeds. Even Tang Ruizong Li Dan, who was considered mediocre, had the honor of quelling the coup and stabilizing Li Tang. However, Li Heng reused the eunuch group and even executed his own son for this purpose. This not only formed the eunuch's monopoly, but also laid the foundation for great trouble for the Tang Dynasty. Later, the eunuch group could not lose its tail, and the long-lasting Anshi Rebellion led to the formation of vassal and town separatist regimes, which became the internal reasons for the demise of the Tang Dynasty.