Manichaeism
Manichaeism is a religion founed in what is now Iran in the 3rd century AD by Mani. It has been viewed as a Christian heresy, but has been argued to be better classified as a new religion, with Mani viewing himself as the final successor in a long line of prophets, beginning with Adam and including Buddha, Zoroaster, and Jesus. It was popular in the West and elsewhere, for a time a competitor to both Christianity and Islam, but disappeared, in part due to persecutions.
Teachings similar to Manichaeism resurfaced during the Middle Ages in Europe in the so-called neo-Manichaean sects, such as the Cathars. They had a strong resemblances to Manichaeism and probably were influenced by it. However, their direct historical links to the religion of Mani are difficult to establish.