what are the cultural and societal influences that have made Hinduism vital to the region in which it originated?

2 answers

Life has always been hard in India -- especially for the millions of poor people. The belief in reincarnation reflects this fact and promises better lives in the future.
Hinduism's growth probably has more to do with the fact of its adaptability.

Hinduism is not as dogmatic as other religious faiths. It developed over many different cultures and many different faiths over a very long period of time.

As a result, it is still developing. And it is growing in many parts of Asia because of that adaptability.