The concept of religion has likely existed since the beginning of human civilization, and different forms of religious practices have existed in various cultures throughout history. The oldest known organized religion is believed to be Zoroastrianism, which originated in ancient Persia (now Iran) around 4,000 years ago. The religion was founded by the prophet Zoroaster and it is based on the worship of one God, Ahura Mazda, and the struggle against the evil spirit Angra Mainyu.
However, many other ancient cultures, such as the Egyptians, Sumerians, and Chinese, also had complex religious beliefs and practices that predate Zoroastrianism. The exact origins of these religions are not well understood and are subject to ongoing scholarly debate.