The Kaiyuan period was a prosperous time in the early years of Emperor Xuanzong of the Tang Dynasty (Li Longji). Tang Xuanzong reigned for 44 years. In the early period (Kaiyuan period), politics was clear, efforts were made to govern, talents were employed, and the economy developed rapidly, advocating culture and education, and the world was supreme. The Tang Dynasty entered its heyday and became the most powerful country in the world at that time. It was called "Kaiyuan Shi Sheng" in history and lasted for 29 years.