Instead of the West gaining power and colonizing much of the world, the East does so. Tang China (中国) survives longer, eventually being replaced by another native Chinese dynasty that crushes the Mongols and moves on to take over much of the world. Japan (日本) and Sri Vijaya (ஸ்ரீ விஜய) also become great powers and compete against each other and with China for colonies and riches. This comes to produce a more Easternized world.
The major point of divergence occurs in 755 CE. An Lushan, the engineer of the OTL An Shi Rebellion, is suspected of treason by Yang Guozhong, a Tang official. Yang Guozhong convinces the Tang emperor to have a spy become close to An Lushan. The spy eventually gets information about the planned rebellion, and An Lushan is executed. Although there are scattered small-scale rebellions during times of drought, the An Shi Rebellion never takes place.