There were several developments in different parts of the subcontinent during the long span of 1,500 years following the end of the Harappan civilisation. This was also the period during which the Rigveda was composed by people living along the Indus and its tributaries.
Agricultural settlements emerged in many parts of the subcontinent, including north India, the Deccan Plateau, and parts of Karnataka. Besides, there is evidence of pastoral populations in the Deccan and further south. New modes of disposal of the dead, including the making of elaborate stone structures known as megaliths, emerged in central and south India from the first millennium BCE.
In many cases, the dead were buried with a rich range of iron tools and weapons. From c. sixth century BCE, there is evidence that there were other trends as well. Perhaps the most visible was the emergence of early states, empires and kingdoms. Underlying these political processes were other changes, evident in the ways in which agricultural production was organised.
Simultaneously, new towns appeared almost throughout the subcontinent. Historians attempt to understand these developments by drawing on a range of sources - inscriptions, texts, coins and visual material. As we will see, this is a complex process. You will also notice that these sources do not tell the entire story.