The most conspicuous outcome of this new insight was the undertaking of multiple archeological excavations throughout Indian subcontinent, followed by systematic study & reading of the rediscovered ancient pillars, rock/cave inscriptions, copper plates and inscriptions on statues. For the first time there was a comprehensive understanding of various dynasties, identities of their rulers, the chronology of their rise & fall and their domains. However, historians were soon facing a new challenge, the rock or pillar inscriptions/records were scarce, often brief (and worn out), and were subject to exaggeration. Here the coins took a paramount role in providing accurate & unbiased information. Further, the evolution of script on coins, dates, designs, coin making process (especially loss of sophistication as reign progressed) and the deteriorating metal content revealed the chronology of rulers within dynasties and the contemporary kingdoms & rulers who copied each other. Significantly, coins identified so many rulers, especially, many Indo-Greek, Kushan & Kshatrapa rulers are known today exclusively because of their coinage.