Historical Vedic religion from c. 500 BCE, declined in India over the 5th to 12th centuries in favor of Puranic Hinduism and Islam. Historical Vedic religion The historical Vedic religion (also known as Vedism, Brahmanism, Vedic Brahmanism, and ancient Hinduism) refers to the religious ideas and practices among Indo-Aryan-speaking peoples of ancient India after about 1500 BCE. These ideas and practices are found in the Vedic texts, and they were one of the major influences that shaped contemporary Hinduism. According to the "Encyclopædia Britannica", in the Hindu tradition and particularly in India, the Vedic religion is considered to be a part of Hinduism.
Ancient Iranian religion in the ancient period. The religious information was rather oral both in composition and transmission. The non-Iranian sources are mainly Greek. The most important Greek source is Herodotus. Some of the Greek information on ancient Iranian religion is however unreliable. This is either because it is based on outright wrong information or based on misunderstandings. The historical reconstruction of ancient Vedic literature is also an important source. The earliest religious texts of the related Indo-Aryan peoples are indispensable for reconstructing the historical development of the ancient Iranian religion. The most important of these texts in this regard is the Rigveda.