The first world religion

Quick, what was the first world religion? — that is, the first religion that expanded well beyond its origins within a given culture and/or political unit.

April DeConick, an expert on Gnostic religion, asserts that Manichaeism was the first world religion. “Who gets taught that in World Religions courses?” DeConick adds. After its start in Persia in the third century, it had expanded to the Atlantic ocean by the fourth century, and along the Silk Road to the Pacific ocean in China by the eighth century or so.