In what year did Hinduism start?

There have been three great migrations in India. The first some 70,000 years ago of the modern humans who came from Africa and spread up to Australia. The second migration which happened some 40,000 years ago may have brought in Dravidians. The third migration may have happened some 10,000 years ago may have brought in the Aryans. All three streams are present in Hinduism even now. The worship of village Gods and Goddess of the aboriginals, the worship of Rama and Krishna of the Dravidians, and the worship by Yajnas of the Aryans. I do not see any abrupt break in the beliefs in India. Even those who conduct Yajnas may be venerating village gods and goddesses. So, I would put Hinduism beginning with the coming of modern humans in India some 70,000 years ago. Hinduism has always been a story of assimilation.

The age of Hinduism:It is impossible to say when Hinduism started.

1. Hinduism was not started by an individual.

2. It is a Holistic religion. Thus, it can't be defined.

2. At one end it is Monotheistic, in the middle it is Polytheistic and at the other end it is Atheistic. Atheism is as old as human beings.

3. Hinduism uses four different kinds of time. Brahmanas use eternal time and thus they believe that Hinduism is eternal. In contrast, Shudras use transient time and thus believe that Hinduism is a very new religion.

4. Hinduism is an analog religion and modern languages are digital. It took thousands of years to start preserving Hinduism in written form. Even today, it is not possible to write correctly about Karma, Moksha and Brahman, using modern languages.

Hinduism - the most mature religion:

Certain facts prove that Hinduism is a very old religion.

Hinduism is the one and only entity, let alone religion, that has analyzed the entire spectrum of human life in immaculate detail and precision. If we decode Hinduism we can know understand all aspects of human life.

Even before other religions started, Hinduism was a highly mature religion.

It declared thousands of years ago that,

1. Man and supreme God are one and the same.

2. All other Hindu gods are derived from the supreme Hindu God Brahman. The fact is that all Hindu gods, like Brahman, are a blend of voluntary (inertial) force and involuntary (kinetic) force.

3. Man can control and be controlled by the supreme God Brahman by attaining Moksha.

Thus, while it is impossible to estimate when Hinduism started, it appears that it is a very old religion. Hinduism is far older than the Vedas.

Nobody really knows when Hinduism started, but we have artifacts of it dating back to almost 28,500 b.c.e. so it started at least then, but probably earlier.
Hinduism is the oldest religion in the entire world. It began as sonn as the world was created
I am not a scholar niether am I a religionist -- but i recall in my childhood (say adolscense) i asked my granpa this very question (who is traditionalist hindu) his answer was all human being who are born in this realm are hindus -- there arose a question then what are those others, he replied -- people convert -- but a human being born is a hindu (the neutral one) rest are all rituals -- conforming to societal values and some traditions (built up over the ages) -- then there is political drama over it, which sometimes manifests itself as a dangerous religious Dogma. All in all his final answer which i understand maybe i wanted to to think like that -- the aim of of life is to be happy and strive for happiness thats how i think hinduism began.
About 300 million years ago in India.
From what I have learned about Hinduism is that it started around 2000BCE but it is hard to tell.

Hope this helps
1500 b.c.

Hinduism is much older than that. It is an indigenous religion and was there since time immemorial. It includes the traditions of the first humans that came to India from Africa, some 70,000 years ago. There never has been any other religion in India in ancient history.