Iron, ideas and the first coins

This was an age of great change, and its effects last till today.

New ideas. New schools of thought grew: late Vedic, Buddhist and Jain, each with its own books. Scholars, monks and nuns travelled across India, and people went on pilgrimages, spreading these teachings. Indian art began to grow again too.

Iron. The Harappans worked copper and bronze. The big change now was iron. People in several regions knew how to make iron from the early 2nd millennium BCE, but it took centuries to become part of daily life. Knowing how to make something and everyone using it are two different things.

By the late 2nd millennium BCE, iron tools were common, so people could farm much more land. More food meant extra to feed cities.

Iron also made better weapons than bronze: lighter and sharper swords, spears and arrows. There is some evidence of wars between neighbouring mahājanapadas (how often, we can't tell), and sometimes alliances. These led to new kingdoms and empires.

Coins. Growing trade made coins necessary. The first Indian coins were silver, a soft metal into which symbols were punched, so they're called punch-marked coins. Later came copper and gold coins. Each mahājanapada usually made its own, but neighbours' coins were used and exchanged in trade too.