Buddhism a Protest to Hinduism or an offshoot?

Few scholars would disagree that at the time of the Buddha, a very heterogeneous and actively developing religious culture flourished in India. This generally accepted historical reality proves that Buddhism was neither a protest against, or an offshoot of Hinduism (this view is even expressed for example in the Encyclopaedia Brittanica). Buddhism simply proved to be one of the more successful new schools of thought within a large variety of philosophies, especially after King Ashoka became a Buddhist in 297 BCE, and turned it into a state religion.

As debate is a very old traditional means of testing (spiritual) teachers in Indian culture, of course one can trace many philosophical works (especially in the Mahayana tradition), that could be interpreted as protesting against, or arguing with other traditions. Western philosophers may have misinterpreted these works as "protest", as such a thing is nearly unthinkable within Western religious systems.

The Buddha himself actually refused to argue on spiritual matters, he explained that he only presented what he had realised as the truth. On the other hand, Buddhism arose from an existing culture, and inevitably many elements of other contemporary traditions are found in Buddhism. In the same sense one could argue that Christianity would be an offshoot of (or protest to) Judaism and Islam is an offshoot of (or protest to) Christianity...

It appears that Buddhism draws most of its inspiration from the religious culture of the Indus Valley civilisation; like the elements of renunciation, meditation, rebirth, karma, and liberation. Also, many symbols of the Indus Valley civilisation. have religious significance and are also sacred to Buddhism. They include the pipal tree (later known as the bodhi tree, or ficus religiosa), and animals such as the elephant and deer. On the other hand, aspects similar to the Aryan tradition can be clearly traced in the rituals of tantric Buddhism. This in contrast to Hinduism, where many of the Aryan principles dominate, although it also contains various elements of the Indus Valley Culture.