During the Tang Dynasty, particularly with the An Lushan Rebellion, an estimated 36 million people died due to conflict and its aftermath. This represented a significant loss of population and was one-sixth of the world's population at the time. The rebellion, which lasted from 755 to 763, caused widespread devastation and disruption. Additionally, famines and natural disasters also contributed to the loss of life during the Tang Dynasty

(http://www.autoadmit.com/thread.php?thread_id=5731737&forum_id=2#48976069)