Religious persecution Buddhism had flourished into a major religious force in China during the Tang period, and its monasteries enjoyed tax-exempt status. Because they didn't contribute taxes, Emperor Wuzong believed Buddhism to be a drain on the state's economy. Coupled with his devotion to Taoism as well and his deep trust in the Taoist monk Zhao Guizhen (), he set out to act against Buddhism, During this first phase, Confucian arguments for the reform of Buddhist institutions and the protection of society from Buddhist influence and practices were predominant. The religious persecution reached its height in the year 845 CE, ultimately confiscating the Buddhist temple properties, destroying 4,600 Buddhist temples and 40,000 shrines, and removing 260,500 monks and nuns from the monasteries. Emperor Wuzong's reasons for doing so were not purely economic. A zealous Taoist, Wuzong considered Buddhism a foreign religion that was harmful to Chinese society. One notable victim of the persecution was the Japanese
Tendai monk
Ennin. Among its purposes were to raise war funds and to cleanse China of foreign influences. As such, the persecution was directed not only towards
Buddhism but also towards other foreign religions, such as
Zoroastrianism,
Nestorian Christianity, and
Manichaeism. Only the native Chinese ideologies of
Confucianism and
Taoism survived the upheaval relatively unaffected. He all but destroyed Zoroastrianism and Manichaeism in China, and his persecution of the growing Nestorian Christian churches sent Chinese Christianity into a decline from which it never recovered. At the same time, Wuzong went far to promote Taoist worship in China through religious regulations and the construction of the
Temple for Viewing Immortals in the Imperial court. (Emperor Wuzong was one of the last Tang emperors and ruled China during a long period of decline; despite his reforms, he was unable to revive the empire through his religious persecutions. After his death, with the help of his uncle Emperor Xuānzong, Buddhism was able to recover from the persecution; but Christianity, Manichaeism, and Zoroastrianism never again played as significant a role in Chinese religious life.)
Dealing with the Uyghur incursions By the time that Emperor Wuzong took the throne, his mother Consort Wei had already died, and he posthumously honored her as an
empress dowager. Also, knowing that Yang Sifu and Li Jue had not supported him as Emperor Wenzong's successor, he had them removed from their offices. He instead installed
Li Deyu, former chancellor under Wenzong, as a chancellor and effectively put most of the responsibilities of governance in his hands. (In 841, Emperor Wuzong further ordered Liu Hongyi and Xue Jileng to commit suicide and planned to order Yang and Li Jue to do so as well, but Yang and Li Jue were spared (and only demoted) after the intercession by Li Deyu and the other chancellors,
Cui Gong,
Cui Dan, and
Chen Yixing.)
The Zhaoyi campaign Immediately after the dissipation of the Uyghur threat, however, Emperor Wuzong faced a crisis of a different kind. In 843,
Liu Congjian the military governor (
Jiedushi) of Zhaoyi Circuit (昭義, headquartered in modern
Changzhi,
Shanxi), who had governed Zhaoyi in
de facto independence from the imperial government and who had a strident rivalry with Qiu Shiliang, was seriously ill, and Liu wanted his adoptive son (and biological nephew)
Liu Zhen to succeed him, and set up the power structure at the circuit to facilitate the transition. He submitted petitions requesting that Liu Zhen be allowed to take over the circuit. When Liu Congjian thereafter died, Liu Zhen sought to inherit the circuit. Li Deyu, believing that this would be a prime opportunity for the imperial government to seize control of Zhaoyi Circuit, advocated a campaign against Liu Zhen, and Emperor Wuzong agreed. Late in Emperor Wuzong's life, he began taking pills made by Taoist
alchemists, which were intended to lead to immortality, and it was said that his mood became harsh and unpredictable as a side effect. By late 845, he was seriously ill. In early 846, in an attempt to ward off the illness, he changed his name to Li Yan—under the theory that under the
Wu Xing cosmology, his original name of Chan () contained two instances of earth () while only containing one instance of water (), which meant that he was getting suppressed by the dynasty's own spirits (as Tang beliefs included that the dynasty was protected by earth), while Yan () contained two instances of fire (), which was more harmonious with earth. Despite this change, his conditions did not get better. The eunuchs, believing that Emperor Wuzong's uncle
Li Yi the Prince of Guang to be simple-minded, decided to make him Emperor Wuzong's successor; they therefore had an edict issued in Emperor Wuzong's name creating Li Yi crown prince (and changing Li Yi's name to Li Chen). Soon thereafter, Emperor Wuzong died after drinking an elixir of immortality, and Li Chen took the throne as Emperor Xuānzong. == Chancellors during reign ==