I am currently reading Josiah Ober's The Rise and Fall of Classical Greece. In the first chapter, “The Efflorescence of Classical Greece,” he offers an interesting account of the economic conditions in Ancient Greek city-states. Here's an excerpt:
The powerful role that specialization and cooperative (mutually beneficial) market exchange can play in promoting economic growth was recognized and described in the later eighteenth century by Adam Smith in the Wealth of Nations. Greek specialization was often more horizontal (workshop and individual craftspeople specializing in the production of specific goods) than vertical (factories employing specialist labor at each phase of a production process). And ancient Greek writers never produced a work of economic analysis to rival Smith’s hugely influential book. Yet it is now very clear that specialization and exchange flourished at different levels in Hellas and, moreover, that the core principles of relative advantage and rational cooperation were understood by the ancient Greeks.According to Ober, the individual Greek city-states had developed specialities based on resource endowments relative to other city-states. The competition, specialization, and cooperation among them gave rise to a culture of innovation and entrepreneurship.