The history of Hinduism covers a wide variety of related religious traditions native to the Indian subcontinent. Its history overlaps or coincides with the development of religion in the Indian subcontinent since the Iron Age, with some of its traditions tracing back to prehistoric religions such as those of the Bronze Age Indus Valley Civilization. It has thus been called the "oldest religion" in the world. Scholars regard Hinduism as a synthesis of various Indian cultures and traditions, with diverse roots and no single founder.