Answer
Sa'd ibn Abi Waqqas may have introduced Islam to China in 651 AD. He was a companion of the Islamic prophet Muhammad and served as a general under the first caliph, Abu Bakr. After Muhammad's death, Sa'd was appointed as the governor of Basra, Iraq. In 651, he led an army to conquer the Sassanid Empire, which was the last pre-Islamic empire in Persia.