Background

Li Chun was born in 778, during the reign of his great-grandfather Emperor Daizong, at the Eastern Palace (i.e., the palace of his grandfather, then-Crown Prince Li Kuo). His father Li Song was Li Kuo's oldest son, and he himself was Li Song's oldest son. His mother was Li Song's concubine Consort Wang. When Li Chun was five or six, by which time Li Kuo was emperor (as Emperor Dezong), there was an occasion when Emperor Dezong held Li Chun on his lap and asked, "Who are you, such that you are in my lap?" His response of, "I am the third Son of Heaven" surprised Emperor Dezong, who thereafter showed him much favor.

As the Prince of Guangling and Crown Prince

In 788, by which time Li Song (Shunzong) was crown prince, Li Chun was created the Prince of Guangling. In 793, he married Lady Guo, a daughter of the deceased general Guo Ai (郭曖) and Emperor Daizong's daughter Princess Shengping, as his wife and princess.

In 804, Li Song (Shunzong) suffered a stroke and became unable to speak. When Emperor Dezong fell gravely ill in spring 805, Li Song was unable to visit him, and Emperor Dezong, distressed over this, died soon thereafter. After Emperor Dezong's death, the eunuchs in the palace initially considered supporting another person as emperor, but due to the objections of the imperial scholars Wei Cigong (衛次公) and Zheng Yin, Li Song was able to assume the throne (as Emperor Shunzong), although during Wei and Zheng's discussion with the eunuchs, the possibility of having Li Chun take the throne directly was mentioned.

As Emperor Shunzong continued to be seriously ill and unable to speak, a group of his close associates—the eunuch Li Zhongyan (李忠言), his concubine Consort Niu, the imperial scholars Wang Shuwen and Wang Pi, and the chancellor Wei Zhiyi—became the key decision-makers. It was said that this group of individuals feared Li Chun for his intelligence and decisiveness, and initially, Li Chun was not created crown prince. However, the eunuchs Ju Wenzhen (俱文珍), Liu Guangqi, and Xue Yingzhen (薛盈珍), all of whom were favored by Emperor Dezong and who lost their power in the new regime, summoned the imperial scholars Zheng, Wei Cigong, Li Cheng, and Wang Ya to the palace to draft an edict for Emperor Shunzong creating Li Chun as crown prince, anyway. Zheng showed a piece of paper to Emperor Shunzong reading, "The Crown Prince should be the oldest son." Emperor Shunzong, who was unable to speak, nodded, and an edict was thereafter issued in late spring 805 creating Li Chun crown prince. The edict also changed Li Chun's name (from 淳 to 純—both rendered "Chun" in modern Mandarin). It was said that Wang Shunwen was so concerned about Li Chun that he was heard reading from Du Fu's poem about the Shu Han regent Zhuge Liang—"He had not even succeeded in his campaigns when he died. This often caused heroes to weep onto their collars." Wang Shuwen and Wei Zhiyi tried to see if their group could persuade Li Chun to favor their positions by having their associate Lu Zhi (陸質) serve as the attendant to Li Chun's studies. However, it appeared that Li Chun disliked Wang Shunwen and his associates, and whenever Lu tried to speak to him on political matters, Li Chun angrily responded, "His Imperial Majesty commissioned you, sir, to teach me about the classics. Why do you discuss other matters?"

By summer 805, a group of military governors (Jiedushi) that Wang Shuwen had disputes with—Wei Gao, Pei Jun (裴均), and Yan Shou (嚴綬)—were submitting petitions to Emperor Shunzong requesting that he let Li Chun serve as regent, and Wei Gao further submitted a petition to Li Chun as well requesting that he take power away from Wang Pi, Wang Shuwen, and Li Zhongyan. On August 26, an edict was issued in Emperor Shunzong's name for Li Chun to serve as regent. Thereafter, the imperial officials began to report to Li Chun. On August 31, Emperor Shunzong further issued an edict yielding the throne to Li Chun, taking for himself the title of "Retired Emperor" (Taishang Huang) and creating Li Chun's mother Consort Wang "Retired Empress." On September 5, Li Chun took the throne (as Emperor Xianzong).

As Emperor

Early reign

Immediately after Emperor Xianzong's ascension to the throne, he purged the government of Wang Shuwen and Wang Pi's associates, exiling them. (He would later order Wang Shuwen to commit suicide.) Emperor Xianzong's father Emperor Shunzong died in spring 806. Some later historians would come to believe that Emperor Shunzong did not die of natural causes, but was murdered by the same eunuchs who had supported Emperor Xianzong's ascension.

Meanwhile, Wei Gao died late in 805, and his deputy Liu Pi seized power of Xichuan Circuit (西川, headquartered in modern Chengdu, Sichuan), which Wei had governed, rejecting the replacement that Emperor Xianzong sent, Yuan Zi. Emperor Xianzong, believing himself to lack the power to attack Liu at this point, initially made Liu the acting military governor. However, Liu then made further demands to be given two neighboring circuits—Dongchuan (東川, headquartered in modern Mianyang, Sichuan) and Shannan West (山南西道, headquartered in modern Hanzhong, Shaanxi)—as well. When Emperor Xianzong refused his demand, he launched an attack on Dongchuan's capital prefecture Zi Prefecture (梓州) in spring 806. At the suggestion of the chancellor Du Huangchang, Emperor Xianzong commissioned the general Gao Chongwen to attack Liu, assisted by the generals Li Yuanyi (李元奕) and Yan Li (嚴礪). In fall 806, Gao captured Xichuan's capital Chengdu and delivered Liu to the capital Chang'an to be executed.

Also in spring 806, Yang Huilin, the nephew of the general Han Quanyi the military governor of Xiasui Circuit (夏綏, headquartered in modern Yan'an, Shaanxi), seized control of the circuit after Han had been ordered to retire and resisted imperial orders. With imperial forces approaching Xiasui's capital Xia Prefecture (夏州), Yang was quickly killed by his own subordinate Zhang Chengjin, ending his rebellion. Around the same time, the warlord Li Shigu, the military governor of the powerful Pinglu Circuit (平盧, headquartered in modern Tai'an, Shandong), died, and his subordinates supported his brother Li Shidao to succeed him. Du advocated trying to divest Pinglu of some of its territory, but Emperor Xianzong, believing that with the campaign against Liu not over by that point, that he should not wage another campaign, and therefore allowed Li Shidao to inherit Pinglu.

After Liu's and Yang's destruction, another warlord, Li Qi the military governor of Zhenhai Circuit (鎮海, headquartered in modern Zhenjiang, Jiangsu) became apprehensive, and, as a means of showing loyalty, requested to go to Chang'an to pay homage to Emperor Xianzong. He did not actually intend to do so, however, and after Emperor Xianzong not only approved, but issued an edict summoning him when he did not depart Zhenhai immediately, rebelled against the imperial government. Before imperial troops could attack him, however, he was captured by his own subordinates and delivered to Chang'an to be executed. Around that time, another warlord, Yu Di the military governor of Shannan East Circuit (山南東道, headquartered in modern Xiangfan, Hubei), fearing Emperor Xianzong, went to Chang'an and yielded control of the circuit to the imperial government, after Emperor Xianzong had ensured Yu's loyalty by marrying his daughter Princess Puning to Yu's son Yu Jiyou (于季友).

In 808, an incident occurred that, as later historians opined, precipitated the later partisan struggles between the "Niu Party" and the "Li Party" that would eventually occur throughout the reigns of the five emperors after Emperor Xianzong. At a special imperial examinations where Emperor Xianzong ordered that low-level officials submit honest opinions about the government, several of the examinees—Niu Sengru, Li Zongmin, and Huangfu Shi (皇甫湜) stated, without using any veiled language, the issues they saw with the governance at the time. The officials that Emperor Xianzong put in charge of the examinations, Yang Yuling and Wei Guanzhi ranked them high. However, the chancellor Li Jifu saw these as severe criticisms of himself, and, weeping, accused the reviewing officials, the imperial scholars Pei Ji and Wang Ya, of conflict of interest—as Huangfu was a nephew of Wang's. As a result of Li Jifu's accusations, Wang, Pei, Yang, and Wei were all demoted, and it was said that while no harm came to Niu, Li Zongmin, and Huangfu at that time, they were effectively stuck at the positions they previously served without promotion. As a result, they all sought positions as staff members of military governors. (Niu and Li Zongmin would later become key leaders of the "Niu Party," while Li Jifu's son Li Deyu would become a key leader of the "Li Party.")

Also around that time, the Shatuo tribes, which had long been vassals of Tang's long-term adversary Tufan, fearing that Tufan was set to move them to the interior of the Tufan state, rebelled against Tufan and surrendered to Tang, under the leadership of Zhuxie Zhiyi (朱邪執宜). They were initially settled at Shuofang Circuit (朔方, headquartered in modern Yinchuan, Ningxia) and later moved to Hedong Circuit (河東, headquartered in modern Taiyuan, Shanxi); their chieftains of the Zhuxie clan were given the area of Huanghuadui (黃花堆, in modern Shuozhou, Shanxi) as their base of operations. (The Shatuo would eventually become a major part of the Tang army, and would yet later yield the ruling families of Later Tang, Later Jin, and Later Han, after Tang's end.)

In 809, after much urging by the imperial scholars (翰林學士, Hanlin Xueshi), led by Li Jiang, that he needed to have a crown prince, Emperor Xianzong created his oldest son Li Ning, born of his concubine Consort Ji, crown prince.

Also in 809, after the death of another warlord, Wang Shizhen the military governor of Chengde Circuit (成德, headquartered in modern Shijiazhuang, Hebei), Emperor Xianzong was initially poised to let Wang Shizhen's son Wang Chengzong inherit Chengde, after Wang Chengzong offered to surrender two of his six prefectures to imperial control. However, after Wang Chengzong reneged on his promise, Emperor Xianzong commissioned the eunuch Tutu Chengcui to command the imperial troops to attack Chengde. (As a result of this campaign's launch, when another warlord, Wu Shaocheng the military governor of Zhangyi Circuit (彰義, headquartered in modern Zhumadian, Henan) subsequently died, he was unable to act against Wu Shaocheng's subordinate Wu Shaoyang, who seized control of the circuit, and was forced to commission Wu Shaoyang, much to the lament of his imperial scholar advisors, who viewed Zhangyi as a far easier target than Chengde.) The campaign against Chengde stalled, however, with one of its original major proponents, Lu Congshi the military governor of Zhaoyi Circuit (昭義, headquartered in modern Changzhi, Shanxi), secretly communicating with Chengde and interfering with the campaign. In summer 810, after Tutu arrested Lu at a feast and allowed the imperial general Meng Yuanyang (孟元陽) to take control of Zhaoyi, Wang agreed to formally submit to Emperor Xianzong, claiming that it was Lu who interfered in his relationship with the imperial government. Emperor Xianzong, seeing that the campaign was making no advances, ended it and made Wang the military governor of Chengde.

Middle reign

After the end of the Chengde campaign, Zhang Maozhao the military governor of Chengde's neighboring Yiwu Circuit (義武, headquartered in modern Baoding, Hebei), who had inherited his position from his father Zhang Xiaozhong, offered to yield the circuit to imperial control, and Emperor Xianzong agreed, sending the official Ren Dijian (任迪簡) to replace Zhang Maozhao. (After Zhang's departure from Yiwu, however, the Yiwu soldiers mutinied against Ren and put him under house arrest, although eventually another group of soldiers then countered their mutiny and restored Ren, allowing Yiwu to be in imperial hands from this point on.) Also in the aftermaths of the Chengde campaign, Tutu Chengcui was demoted and, later, after he was involved in a corruption scandal, sent out of the capital to serve as the eunuch monitor for Huainan Circuit (淮南, headquartered in modern Yangzhou, Jiangsu).

In 811, at Li Jifu's suggestion, Emperor Xianzong appointed several officials—Duan Pingzhong (段平仲), Wei Guanzhi, Xu Mengrong (許孟容), and Li Jiang—to review the governmental structure, to streamline it, reduce the number of officials who were not carrying out any crucial tasks, and revise the officials' wage scale. Later in the year, with Emperor Xianzong believing that Li Jifu had often used his own personal likes and dislikes to decide on his policies, he promoted Li Jiang to be a chancellor as well, to counterbalance Li Jifu.

Around the new year 812, Li Ning died. In fall 812, Emperor Xianzong created another son Li You the Prince of Sui, born of his wife, Consort Guo (formerly the Princess of Guangling), crown prince and changed Li You's name to Li Heng, even though he had an older son, Li Kuan (李寬) the Prince of Li, as it was viewed by officials such as Cui Qun that Li Heng, born of a wife rather than a concubine, was the proper heir. Still, despite repeated petitions by the officials to create Consort Guo empress, Emperor Xianzong was apprehensive that, because of the prominent bloodlines that Consort Guo represented (being the granddaughter of the great general Guo Ziyi and the daughter of a princess), if she were created empress, other consorts would not dare to have sexual relations with him, and therefore repeatedly formed excuses with regard to not being able to find the right date to do so. He would eventually never create her (or any other consort) empress.

Later in 812, the warlord Tian Ji'an the military governor of Weibo Circuit died. With Tian Ji'an's son and designated successor Tian Huaijian being young, soon thereafter, the soldiers mutinied and supported Tian Ji'an's relative Tian Xing. Tian Xing offered to subject Weibo to imperial commands, and soon thereafter, Emperor Xianzong made Tian Xing the military governor of Weibo and changed his name to Tian Hongzheng. With Tian Hongzheng as Weibo's military governor, for the rest of Emperor Xianzong's reign, Weibo became obedient to the imperial government.

In 814, Wu Shaoyang died. Emperor Xianzong did not confirm Wu Shaoyang's son Wu Yuanji as his successor. In response, Wu Yuanji began attacking the nearby circuits to create pressure on the imperial government. Emperor Xianzong declared a general campaign against Wu Yuanji. Wu sought aid from Li Shidao and Wang Chengzong, who repeatedly petitioned Emperor Xianzong to pardon Wu Yuanji, to no avail. Li Shidao thereafter retained a group of assassins to carry out guerilla warfare tactics around the eastern capital Luoyang, to try to disrupt the campaign against Zhangyi and to create a sense of terror among the officials and the people. When the imperial pressure on Zhangyi still being unrelenting, with the imperial generals Wu Chongyin and Li Guangyan frequently dealing Zhangyi troops defeats (although imperial troops were unable to decisively defeat Zhangyi), Li Shidao decided to assassinate the chancellor Wu Yuanheng, whom Emperor Xianzong had put in charge of the campaign against Zhangyi, as well as the official Pei Du, a major proponent of the campaign. In summer 814, assassins that Li Shidao sent killed Wu Yuanheng and wounded Pei, terrifying the officials and the people at Chang'an. Emperor Xianzong's resolve against Zhangyi did not change, however, and when he came to believe that Wang was responsible for the assassination, he declared a general campaign against Wang as well. He also promoted Pei to be a chancellor. (Later, after investigations by Lü Yuanying the defender of Luoyang after a plot by Li Shidao's subordinates to riot at Luoyang was foiled, Emperor Xianzong found out that Li Shidao was responsible for Wu Yuanheng's assassination, but by that point, as he was already waging campaigns against Wu Yuanji and Wang, he could not, and did not, declare yet another campaign against Li Shidao as well at that point.)

Late reign

The imperial forces sent against Zhangyi and Chengde were unsuccessful in quickly achieving final victory against them, however. In 817, with suggestion from the chancellor Li Fengji that he should concentrate on one campaign, Emperor Xianzong called off the campaign against Chengde (although he did not pardon Wang). Meanwhile, Pei Du volunteered to head to the Zhangyi front to oversee the operation, and Emperor Xianzong agreed. Later in the year, Li Su the military governor of Tangsuideng Circuit (唐隨鄧, headquartered in modern Zhumadian) launched a surprise attack against Zhangyi's capital Cai Prefecture (蔡州), catching its defenders off guard and capturing it, seizing Wu Yuanji. Wu was subsequently delivered to Chang'an to be executed, and the imperial troops under Pei took over Zhangyi.

After Wu Yuanji's execution, Li Shidao and Wang Chengzong both became fearful. In 818, Wang offered to surrender two prefectures to imperial control and send his two sons to Chang'an to serve as hostages. He also sought intercession from Tian Hongzheng. With Tian also requesting that Emperor Xianzong accept his offer, Emperor Xianzong did so, merging the two prefectures that Wang surrendered into neighboring Henghai Circuit (橫海, headquartered in modern Cangzhou, Hebei), which had been obedient to the imperial government. Li Shidao also offered to surrender three of his 12 prefectures to imperial control and send his son as a hostage—but soon reneged on the offer. Emperor Xianzong thus declared a general campaign against his Pinglu Circuit, and soon, the imperial forces were repeatedly dealing defeats to Pinglu troops.

Meanwhile, it was said that after the victory over Zhangyi, Emperor Xianzong began to be arrogant and extravagant in his lifestyle, and he favored such officials as Huangfu Bo and Cheng Yi, whom he believed to be capable of increasing revenues for palace use. He eventually made both Huangfu and Cheng chancellors, despite earnest pleas by Pei and Cui Qun, who was a chancellor by this point as well, against the move. It was said that Huangfu soon was speaking against Cui and Pei, causing both to be sent out of the capital. In spring 819, there was an occasion when Emperor Xianzong had what was alleged to be Gautama Buddha's finger bone escorted from a temple in Fengxiang (鳳翔, in modern Baoji, Shaanxi) to the palace in a grand ceremony, kept the bone in the palace for three days, and encouraged the people to worship it and make donations to the temples. When the official Han Yu spoke against it, Han was exiled to be the prefect of Chao Prefecture (潮州, in modern Chaozhou, Guangdong).

Also in spring 819, after Li Shidao became suspicious of his officer Liu Wu, who was then resisting Tian's attack, and secretly ordered Liu's deputy Zhang Xian to execute Liu and take over the troops. Zhang, who was friendly with Liu, revealed Li Shidao's orders to Liu. Liu responded by launching a surprise attack on Pinglu's capital Yun Prefecture (鄆州), capturing Li Shidao and his sons and executing them, delivering their heads to Chang'an. Emperor Xianzong made Liu, who had expected to succeed Li Shidao, the military governor of Yicheng Circuit (義成, headquartered in modern Anyang, Henan), and divided Pinglu into three circuits to weaken it and keep its territory under imperial control.

By this point, Emperor Xianzong was taking medicines made by the alchemist Liu Mi (柳泌), who claimed that he could bring the emperor immortality. It was said that as a result of these medicines, Emperor Xianzong was becoming increasingly thirsty and irritable. It was said that he was so easily angered that the eunuchs serving him were often punished or even executed for minor faults, causing them to be fearful of him. In spring 820, he died suddenly, and it was commonly believed that he was assassinated by the eunuch Chen Hongzhi. It was said, however, that Chen's eunuch colleagues declared that Emperor Xianzong had died from Chinese alchemical elixir poisoning due to the medicines that he was taking. Tutu Chengcui tried to support Li Kuan, who had been renamed Li Yun (李惲), to succeed Emperor Xianzong, but the other eunuchs Liang Shouqian (梁守謙), Ma Jintan, Liu Chengjie, Wei Yuansu (韋元素), and Wang Shoucheng, supported Li Heng, and they killed Tutu and Li Yun. Li Heng thereafter became emperor (as Emperor Muzong). (Another son of Emperor Xianzong's, Li Yi, after he became emperor in 846, would come to suspect that Consort Guo and Li Heng were involved in Emperor Xianzong's assassination, but no direct evidence tied them to the assassination.)

Chancellors during reign

• Du You (805–812)

• Jia Dan (805)

• Wei Zhiyi (805)

• Du Huangchang (805–807)

• Yuan Zi (805)

• Zheng Yuqing (805–806)

• Zheng Yin (805–809)

• Wu Yuanheng (807, 813–815)

• Li Jifu (807–808, 811–814)

• Yu Di (808–813)

• Pei Ji (808–810)

• Li Fan (809–811)

• Quan Deyu (810–813)

• Li Jiang (811–814)

• Zhang Hongjing (814–816)

• Wei Guanzhi (814–816)

• Pei Du (815–819)

• Li Fengji (816–817)

• Wang Ya (816–818)

• Cui Qun (817–819)

• Li Yong (817–818)

• Li Yijian (818)

• Huangfu Bo (818–820)

• Cheng Yi (818–819)

• Linghu Chu (819–820)

• Han Hong (819–820)

Family

Consorts and Issue:

• Empress Yi'an, of the Guo clan of Huayin (懿安皇后 華陰郭氏; d. 851), first cousin once removed, personal name Nianyun (念雲)

　• Li Heng, Muzong (穆宗 李恆; 795–824), third son

　• Princess Qiyang Zhuangshu (岐陽莊淑公主; d. 837), 11th daughter

　　• Married Du Cong of Jingzhao, Duke Bin (京兆; 794–873) in 814, and had issue (two sons, two daughters)

• Empress Xiaoming, of the Zheng clan (孝明皇后 鄭氏; d. 865)

　• Li Chen, Xuanzong (宣宗 李忱; 810–859), 13th son

　• Princess Anping (安平公主)

　　• Married Liu Yi (劉異)

• Taiyi, of the Xu clan (太儀 許氏)

　• Princess Nankang (南康公主)

　　• Married Shen Fen (沈汾)

• Taiyi, of the Yang clan (太儀 楊氏)

　• Li Yue, Prince Qiong (瓊王 李悅; d. 840), ninth son

• Meiren, of the Ji clan (美人 紀氏)

　• Li Ning, Crown Prince Huizhao (惠昭皇太子 李寧; 793–812), first son

• Lady, of the Du clan (杜氏)

　• Li Xun, Prince Mian (沔王 李恂; 808–844), tenth son

• Lady, of the Zhao clan (趙氏)

　• Li Yin, Prince Mao (茂王 李愔; 809–853), 12th son

• Unknown

　• Li Yun, Prince Li (澧王 李惲; d. 820), second son

　• Li Cong, Prince Shen (深王 李悰), fourth son

　• Li Xin, Prince Yang (洋王 李忻; 801–828), fifth son

　• Li Wu, Prince Jiang (絳王 李悟; 797–827), sixth son

　• Li Ke, Prince Jian (建王 李恪; 805–821), seventh son

　• Li Jing, Prince Fu (鄜王 李憬; d. 839), eighth son

　• Li Yi, Prince Wu (婺王 李懌), 11th son

　• Li Xie, Prince Zi (淄王 李恊; d. 836), 14th son

　• Li Dan, Prince Heng (衡王 李憺), 15th son

　• Li Chong, Prince Chan (澶王 李㤝), 16th son

　• Li Zhui, Prince Di (棣王 李惴), 17th son

　• Li Ti, Prince Peng (彭王 李惕), 18th son

　• Li Tan, Prince Xin (信王 李憻; d. 867), 19th son

　• Li Ce, Prince Rong (榮王 李㥽; 815–880), 20th son

　• Princess Lianghuikang (梁惠康公主), first daughter

　　• Married Yu Jiyou of Henan (河南 於季友), the fourth son of Yu Di, in 807

　• Princess Yongjia (永嘉公主)

　• Princess Hengyang (衡陽公主)

　• Princess Xuancheng (宣城公主), sixth daughter

　　• Married Shen Chai (沈𥐟)

　• Princess Zhengwenyi (鄭溫儀公主)

　　• Married Wei Rang (韋讓) in 816, and had issue (four sons, three daughters)

　• Princess Chenliu (陳留公主)

　　• Married Pei Sun of Hedong (河東 裴損)

　• Princess Zhenning (真寧公主), second daughter

　　• Married Xue Hong of Hedong (河東 薛翃) in 806

　• Princess Linzhen (臨真公主)

　　• Married Wei Zhu (衛洙)

　• Princess Pukang (普康公主)

　• Princess Zhenyuan (真源公主)

　　• Married Du Zhongli (杜中立)

　• Princess Yongshun (永順公主)

　　• Married Liu Hongjing (劉弘景)

　• Princess Yong'an (永安公主), ninth daughter

　• Princess Yining (義寧公主)

　• Princess Ding'an (定安公主), fifth daughter

　　• Married Chongde (崇德可汗; d. 824) in 821

　• Princess Gui (貴公主)

Ancestry

生平

身世

唐代宗大曆十三年（778年）陰曆二月十四日，李淳（唐憲宗）在長安之東內（大明宮）內出生。

當時的皇帝是他的曾祖父唐代宗，祖父唐德宗時為皇太子。父唐順宗為郡王，母莊憲皇后王氏是父親的妾室。

後來，祖父唐德宗削藩失敗，長安發生涇原兵變，祖父唐德宗和6歲的李淳出逃。及後唐德宗抱著李淳揶揄地問道：「小孩，你是誰家的孩子？」自幼聰慧的李淳回答：「我是唐朝第三個天子！」（唐德宗為天子、父親是未來的天子、自己將是第三個天子。）唐德宗被他嚇了一跳，並十分佩服他的智慧。不出所料，長大後的李淳愛讀貞觀政要，以太宗和玄宗作榜樣，立志削藩，恢復大唐威名。

封為郡王

貞元四年（788年），封為廣陵郡王。

貞元九年（793年）十一月丁卯，納妃郭氏。同年，長子李寧出生。

永貞內禪

貞元二十一年（805年）初，父親唐順宗繼位，唐順宗重用王叔文、韋執誼、柳宗元、劉禹錫等官員，王叔文集團試圖進行永貞改革，抑制宦官勢力。

但當時唐順宗有中風、癱瘓的情況。不滿改革的宦官俱文珍、劉光琦等人聯合劍南節度使韋皋、荊南節度使裴均、河東節度使嚴綬等外藩，迫使唐順宗立李淳為太子，改名李純，七月，太子監國。八月，俱文珍又迫唐順宗退位為上皇，傳位予長子唐憲宗，史稱永貞內禪。王叔文等二王八司馬皆被貶謫。

元和元年正月，上皇駕崩，官方說法為病死。野史影射順宗是被宦官謀殺而死，可見於唐人傳奇《辛公平上仙》。

在位生涯

唐憲宗繼位後，決心「以法度裁制藩鎮」，開始對割據的藩鎮開展了一系列戰爭，他在繼位的次年就開始對西川節度副使劉闢開戰獲勝，同年夏綏軍留後楊惠琳不肯交出他的兵權，憲宗也征討他，惠琳敗死。

元和二年（807年），討伐鎮海軍節度使李錡。

元和七年（812年），魏博節度使田興歸服唐朝，同年他開始對抗拒唐朝的成德節度使王承宗作戰，但沒有能夠獲勝，從元和十年（815年）到元和十二年（817年）唐鄧節度使李愬平定了淮西吳元濟的叛亂，史稱雪夜征淮西，當時唐隨軍主簿即參謀長即韓愈，韓且寫凱旋勝碑文留于淮西。

元和十三年（818年），發五道兵討淄青節度使李師道。吳元濟被平定後，全國所有藩鎮至少名義上全部歸服唐朝。唐朝出現短暫統一，「至是盡遵朝廷約束。」史稱「元和中興」。

元和十四年（819年）正月，憲宗遣使往鳳翔迎釋迦牟尼佛遺骨入宮供奉，刑部侍郎韓愈上「論佛骨表」勸諫，言語不敬，皇帝大怒，差點處死了韓愈，不過最後只將韓貶為潮州刺史。這次迎佛骨陣容浩大，《資治通鑒》載「中使迎佛骨至京師，上留禁中三日，乃歷送諸寺。王公士民瞻奉舍施，唯恐不及。有謁戶充施者，有燃香燒頂供養者。」

暴斃疑雲

憲宗的帝位是由宦官擁立的，因此憲宗重用宦官，軍隊中許多將領與監軍由宦官擔任，有些宦官擁有很高的軍權，但憲宗對宦官亦不優待，其後期好長生不老之術，多服金丹，「日加躁渴」，性情暴躁易怒，動輒責罰左右黃門，宦官們不堪鞭笞。

元和十五年（820年）陰曆正月二十七日，憲宗暴卒，據說是被宦官內常侍陳弘志和王守澄合謀毒死。一說是宦官叫唆十餘名宮女，集體悶死他，史上第二位被女人殺害的皇帝（第一位被女人殺害的皇帝是晉孝武帝，為張貴人所弒），享年42歲，在位15年，謚聖神章武孝皇帝。大中三年，加謚昭文章武大聖至神孝皇帝。

王夫之在其《讀通鑑論》中推理認為憲宗之暴斃實則是郭氏（穆宗生母）與穆宗縱逆之所為。

家庭

家世

唐憲宗李純的祖先

后妃

孝明皇后、紀美人與餘十七王之母，原皆屬後宮一般姬侍婢妾，因生宣宗和皇太子寧留下姓氏。出身高貴的只有生穆宗的懿安皇后。

皇后

• 懿安皇后郭氏，名將郭子儀孫女、郭曖與昇平公主長女，憲宗元配妻子，卻只被冊為貴妃，而非皇后。其子繼位，是為穆宗。尊為皇太后。是敬宗、文宗、武宗的祖母，均尊為太皇太后。宣宗即位，仍尊嫡母為太皇太后。宣宗年間，郭太皇太后欲跳承天樓自盡，當夜暴崩，喪事未得到元配皇后應有的禮儀。直到宣宗駕崩，懿宗即位，郭氏才配享憲宗。郭氏是唐代第一位太皇太后，一生歷經唐朝七代皇帝，其中五朝極盡尊貴，是所謂七朝五尊。

• 孝明皇后鄭氏，原為郭貴妃宮婢。憲宗駕崩後，隨子封為光王太妃。其子即位為唐宣宗後尊為皇太后。以懿宗祖母身份成為太皇太后，這也是唐朝第二與最後一位太皇太后。

妃

• 王賢妃，除《唐會要·卷二十一·列傳第二十一》記陪葬景陵外，無其它記錄

• 紀妃，與紀美人是否一人無考

嬪

• 何昭儀

•

• 薛太儀（799年—867年七月初六），葬在萬年縣長樂鄉王徐村，故薛太儀墓誌銘提及

• 楊太儀，瓊王生母。

世婦

• 孟婕妤，生平不詳，追贈婕妤，史書無載，見于白居易在元和二年（807年）為其所書的祭文

• 紀美人，與紀妃是否同一人無考。

• 許美人，唐順宗逝世後的元和元年八月甲子，與唐順宗生育子女的妾室同時冊封，是否是唐順宗未生育子女的妾室，無法考証。

• 尹才人，元和元年八月甲子冊封

• 段才人，元和元年八月甲子冊封

•

其他宮人

• 杜氏，沔王李恂生母，其子李恂墓誌僅稱杜氏，已無法考証其妃嬪封號

• 趙氏，茂王李愔生母，類似于杜氏

• 鄭氏，鄭國溫儀公主生母，鄭國溫儀公主墓誌稱生母鄭氏，已無法考証其妃嬪封號

• 杜秋娘 《資治通鑑》稱杜仲陽，李錡正式起兵造反。後來李錡造反失敗，杜秋被納入宮中。

子女

子

憲宗二十子，紀美人生惠昭太子李寧，懿安皇后生唐穆宗李恆、絳王李悟，孝明皇后生唐宣宗李忱；其他十六王，皆後宮所生。

• 平原郡王→鄧王→皇太子→惠昭太子李寧（母紀美人）

• 同安郡王→澧王李惲（本名李寬）

• 遂王→唐穆宗李恆（母郭貴妃）

• 彭城郡王→深王李悰（本名李察）

• 高密郡王→洋王李忻（本名李寰）

• 文安郡王→絳王李悟（本名李寮）

• 建王李恪（本名李審，被追封為南唐定宗）

• 鄜王李憬

• 瓊王李悅（母太儀楊氏）

• 沔王李恂（母杜氏）

• 婺王李懌

• 茂王李愔（母趙氏）

• 光王→唐宣宗李忱（母鄭宮人）

• 淄王李恊

• 衡王李憺

• 澶王李㤝

• 棣王李惴

• 彭王李惕

• 信王李憻

• 榮王李㥽

女

唐憲宗共有18位女兒：

• 梁國惠康公主（先封為普寧公主，下嫁于季友）

• 永嘉公主（出家為道士）

• 衡陽公主（夭折）

• 宣城公主（下嫁沈（立+義））

• 鄭國溫儀公主（先封為汾陽公主，下嫁韋讓）

• 岐陽莊淑公主（母郭貴妃，下嫁杜悰）

• 陳留公主（下嫁裴損）

• 真寧公主（下嫁薛翃）

• 南康公主（母許太儀，下嫁沈汾，薨于咸通年間）

• 臨真公主（先封為襄城公主，下嫁衛洙，薨于咸通年間）

• 普康公主（夭折）

• 真源公主（先封為安陵公主，下嫁杜中立）

• 永順公主（下嫁劉弘景）

• 安平公主（母鄭宮人，下嫁劉異，薨于乾符年間）

• 永安公主（唐穆宗第九妹，出家為道士）

• 義寧公主（夭折）

• 定安公主（唐穆宗第五妹，先封為太和公主，下嫁回鶻崇德可汗）

• 貴鄉公主（夭折）

另《唐會要》誤將李悟女壽安公主列為唐憲宗養女、琛王之女。

關聯條目

• 永貞內禪

• 元和中興

• 辛公平上仙