The Early Classical Era in India

Kuru was the main powerful vadic kingdom, but it soon came under attack by non vadic tribes. They were gradually weakened, and vadic society basically had to move further east into the lower gangetic plan around what's now behar. And also some moved up into the safety of the mountains, and you get avatic society in napal. After about 600 b c, there's a renewed orbanization, a new growth and flourishing of cities, which then soon gives rise to the classical era,. The era of great, unifying empires in india.