Emperor Xuanzong of Tang, also commonly known as Emperor Ming of Tang or Illustrious August, personal name Li Longji, was the seventh emperor of the Tang dynasty in China, reigning from 713 to 756 CE. His reign of 43 years was the longest during the Tang dynasty. In the early half of his reign he was a diligent and astute ruler. Ably assisted by capable chancellors like Yao Chong, Song Jing and Zhang Yue, he was credited with bringing Tang China to a pinnacle of culture and power. Emperor Xuanzong, however, was blamed for over-trusting Li Linfu, Yang Guozhong and An Lushan during his late reign, with Tang's golden age ending in the An Lushan Rebellion.