Overview
Wang Yu (died July 6, 768) was a Chinese politician during the Tang dynasty, who became trusted by Emperor Suzong due to his studies in witchcraft and the employment of such witchcraft on Emperor Suzong's behalf, such that Emperor Suzong eventually made him chancellor.
Background
It is not known when Wang Yu was born. He was a fifth-generation descendant of Wang Fangqing, who served as a chancellor during the reign of Wu Zetian. His intervening ancestors' names were recorded as Wang Jiao, Wang Chong, Wang Zhonglian, and Wang Shao, none of whom was recorded to have carried any official titles except for Wang Jiao who served as prefect of Lu Prefecture and Wang Zhonglian who served as a secretarial officer at Yang Prefecture (揚州, roughly modern Yangzhou, Jiangsu). Wang Yu himself was said to be well-studied in the worshipping of gods and spirits and particularly paid attention to the proper times to offer sacrifices.
During Emperor Xuanzong's reign
Toward the end of the Kaiyuan era (713-742) of Wu Zetian's grandson Emperor Xuanzong, Emperor Xuanzong was paying great attention to Taoist doctrines and ceremonies. Wang Yu made a submission to Emperor Xuanzong requesting that an altar, to be called the Spring Altar (春壇, Chun Tan), be built to the east of the capital Chang'an and dedicated to the Blue Emperor (青帝, Qing Di). Emperor Xuanzong agreed, and he made Wang an official-scholar at the ministry of worship (太常寺, Taichang Si) and an imperial censor (侍御史, Shiyushi), as well as a special emissary of worship (祠祭使, Ciji Shi). It was said that Wang drew favors from the emperor due to his dedication to worshipping gods on Emperor Xuanzong's behalf. It was further said that while previously, the common populace already had a custom of sacrificing joss paper to the spirits, it was Wang who brought this custom into official ceremonies.
During Emperor Suzong's and Emperor Daizong's reigns
After Emperor Xuanzong's son Emperor Suzong became emperor in 756, Wang Yu was promoted to be the minister of worship (太常卿, Taichang Qing). Because his worship of the gods pleased Emperor Suzong, Emperor Suzong often gave him rewards. In 758, when Emperor Suzong removed the chancellors Cui Yuan and Li Lin from their posts, he made Wang Zhongshu Shilang -- the deputy head of the legislative bureau of government (中書省, Zhongshu Sheng) and gave him the designation Tong Zhongshu Menxia Pingzhangshi, making him a chancellor de facto.
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