An Advance in Sid Meier's Civilization.
Modern banking arose during the Renaissance among the merchant families of the Italian city-states. These families benefited from the increase in trade, both with the Middle East and within Europe. Wealthy merchants pooled their surplus money into a bank, then loaned cash (with interest) to other commercial enterprises. The availability of this capital for investment made many new businesses possible, accelerating economic growth.
Prerequisites: Trade and The Republic.
Allows for: Industrialization.