Qin Shi Huang was the first emperor of the Qin dynasty in China in the 3rd century BC. (COMIC: The Immortal Emperor; AUDIO: The Emperor of Eternity)
As a boy, Qin Shi Huang rescued an alien from the wreckage of a "star chariot". He came to know the alien as his first general and most trusted advisor, Meng Tian. Using Meng's knowledge, Qin Shi Huang united the Warring States, making him the First Emperor. Following a failed assassination attempt, Qin Shi Huang had Meng build him a new, indestructible body, making him a cyborg. He also sought immortality.
Meng, seeking to take control of Earth, later remotely activated the Terracotta Army, and switched off Qin Shi Huang in his throne room, describing him as a puppet who had outlived his usefulness. Donna Noble used her mobile phone to interrupt the signal paralysing the Emperor, waking him up again. While Qin Shi Huang and Meng were fighting each other, Meng shot at the warp converter, which shut down the Emperor and the Army, while also burying the whole palace in an explosion. According to the Tenth Doctor, no-one knew how he died. The Doctor said that archaeologists were due to excavate both the Emperor and his tomb around the early 21st century. (COMIC: The Immortal Emperor)