When was the mural of Mogao Grottoes in Dunhuang, Gansu Province first created? What is the content of the main painting?

The existing murals in Dunhuang Mogao Grottoes in Gansu Province cover an area of 45,000 square meters. It is a master of Chinese ancient mural art. It was first created in the Northern Wei Dynasty, and it is necessary to draw stories about Buddhism, origin and karma. Sui and Tang Dynasties reached unprecedented prosperity, with rich themes and bright colors. In addition to the original content, there are new paintings such as paintings, Buddhist induction story paintings, sacrificial portraits, and Swiss portraits. Since the Northern Song Dynasty, there has been little innovation in the theme of Dunhuang murals.