Hinduism or the Vedic culture originated with a race of the Aryans who came to the Indian subcontinent thousands of years before the birth of Christ. They came with their own culture, which soon began to evolve based on a new environment and new needs. The changes these Aryans first brought into their way of life were the beginnings of Hinduism.
The original homeland of the Aryans is referred to in the Zoroastrian scripture Vendidad as the lost Airyane Vaejahi or the seed land of the Aryans. It was possibly located in the Russian steppes of Central Asia. It is believed that sometime during the last ice age the Aryans were forced to migrate from their homeland and seek more habitable lands to the southwest and southeast. The westward journeys took them to the nations of Europe such as Greece, Italy, Germany, France, Scandinavia and the British Isles. The eastward journey took them first to Persia (modern day Iran) and later through the Khyber and Bolan passes, across the River Indus to their new home. It is impossible to date with precision these migrations to India. They definitely occurred before 1500 BCE, but some sources place them as early as 6000 BCE. Also to be noted is the fact that these migrations were not a one-time movement but consisted of several movements separated by long periods in which the immigrants settled in different parts of the Indo-Gangetic plain, the fertile land formed by the rivers Indus and Ganga and their tributaries.
The Sanskrit name for the river Indus was Sindhu meaning a great body of water. It was this river that formed the divide. Over a period of time those to the west of the Indus began to refer to those to the east of the Indus as Hindus, a word derived from Indus or Sindhu. Gradually the area bounded by the rivers Indus and Brahmaputra in the north and the triad of seas (the Arabian Sea, the Indian Ocean and the Bay of Bengal) in the south became the homeland of the Hindus. The Indus and the Brahmaputra both have their source in the Mansarovar Lake now in Tibet.
The Aryans were not the first immigrants to India. Many thousands of years before them had come a race known as Dravidians. When the Dravidians came to this fertile land they encountered the original tribes of this area, whom they pushed towards the south. In turn the Dravidians were pushed south by the Aryans and tribal aborigines forced to occupy the most inhospitable hills and forests, where their descendants can still be found.
The Aryans initially handed down their scriptures orally from generation to generation taking care not to mix them with the beliefs and practices of the other cultures. But when such interaction became inevitable, the Aryan seers thought it fit to record the scriptures, so that despite subsequent intermingling the pristine form would be preserved. By this time Sanskrit had become the spoken language and was the ideal choice for recording the scriptures. The hymns were compiled according to their functions, with each compilation containing hymns from a large period of time. Thus the four Vedas came into existence. The earliest Vedas bear direct references to the Iranian deities like Varun, Usha and Mitra. Soon the truly Hindu deities began to be worshipped. This was a period of a struggle for supremacy not only between the Aryans and Dravidians but between the different clans of the Aryans as well. A powerful warrior deity was required to lead them in battle and so Indra the king of the demi-Gods began to be worshipped.
For a later alternative theory please check out The Reverse Aryan Invasion.
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