Jainism during Indus Valley Civilization
According to some expert viewpoints Jainism might have existed in the Indus Valley Civilization including other Sramanic movements, historians are just not finding that in Jain oral traditions but guess like the vedic oral traditions. It is possible that Jainism might have preserved oral traditions but they have not been dated yet by the linguists.
Jainism is supposed to be the oldest and recognized as a religion at approximately 1800 to 2000BC. It precedes Buddhism by about 500 years or so. As per the king lists given in various Puranas, names of Rishabh, Bharat, Bahubali are mentioned. But the Indus Valley civilization seems to be much older than that.