What was the social organization in the early and later Vedic period?

The Vedic period in India takes its name from the Vedas, Sanskrit-language texts from the sixteenth century BCE to the ninth century BCE. In the early period, people were organized into clans (vish); each was headed by a raja, meaning chief or king. He had a responsibility to protect the clan, especially in war. The earlier pastoral nomadism gave way to settled, mixed pastoral and agricultural communities in which cows were especially important. Kinship organization was patriarchal with endogamous marriage. Clans gathered for several types of assemblies and for sacrificial rituals.
In the later Vedic period, a geographical delimitation of peoples and their territory arises; the ruling clans called aryas gave rise to the people's Aryan designation and their territory—much of it near the Ganges—as Aryavarta. Over the course of this period, with eastward expansion, the importance of clan identity ceded to that of territorial identity; the settlement areas showed increasing urbanization and gradually became states, often named for the clans.
By the fifth century BCE, kingdoms largely replaced chiefdoms, with the rulers advised by numerous professional representatives. Smaller assemblies continued but the larger ones decreased. The role of king became more permanent; with the increasingly frequent and elaborate ceremonies and related sacrifices, the role of priests also gained importance. This was reified into the origins of the varna system, which included the designation of highest rank to the priests, Brahmans, followed by members of landowning families with military power: the Kshatriyas.
https://www.britannica.com/place/India/Early-Vedic-period