Guan Yu, courtesy name Yunchang, was a Chinese military general serving under the warlord Liu Bei during the late Eastern Han dynasty of China. Guan Yu played a significant role during the end of the Han Dynasty and the establishment of Liu Bei's state of Shu Han during the Three Kingdoms period.
Guan Yu's life was lionised and his achievements glorified to such an extent after his death that he was deified during the Sui dynasty. Through generations of storytelling, culminating in the 14th-century historical novel Romance of the Three Kingdoms, his deeds and moral qualities have been given immense emphasis, making Guan Yu one of East Asia's most popular paradigms of loyalty and righteousness. In religious devotion he is reverentially called the "Emperor Guan" (Guān Dì) or "Lord Guan" (Guān Gōng). He is a deity worshipped in Chinese folk religion, popular Confucianism, Taoism and Chinese Buddhism.
Temples and shrines dedicated exclusively to Guan Yu can be found across mainland China, Hong Kong, Macau, Taiwan, Malaysia, Singapore, Vietnam, South Korea, Japan, Australia, etc.
The 13th of the 1st lunar month, 13th of the 5th lunar month and 24th of the 6th lunar month are feasts days of Guan Di.