Manichaeism was one of the major Iranian Gnostic religions, originating in Sassanid Persia. Although most of the original writings of the founding prophet Mani (c. 216??76 CE) have been lost, numerous translations and fragmentary texts have survived.

Manichaeism taught an elaborate cosmology describing the struggle between a good, spiritual world of light, and an evil, material world of darkness. Through an ongoing process which takes place in human history, light is gradually removed from the world of matter and returned to the world of light from which it came. Its beliefs can be seen as a synthesis of Christianity, Zoroastrianism and Buddhism.

Manichaeism thrived between the third and seventh centuries, and at its height was one of the most widespread religions in the world. Manichaean churches and scriptures existed as far east as China and as far west as the Roman Empire. Manichaeism survived longer in the east, and appears to have finally faded away after the 14th century in southern China.