The idea of the central bank was born in the Middle Ages, when failures of the largest merchant banks of that era, founded by the Bardi and Peruzzi families, shocked the Italian City-State of Florence in 1343 and 1346. These financial crises gave birth to the idea that the commercial banking sector would need a "liquidity backstop," i.e., an entity that could lend to private financial institutions in trouble. This was the original aim of central banks: to act as piggy banks for solvent commercial banks with temporary liquidity problems.

The first central bank that resembled the modern ones emerged in 1609, when the Dutch empire created an exchange bank, Wisselbank, to convert foreign coins into domestic currency. The central bank of Sweden, the Riksbanken, was created in 1668, and the Bank of England (BoE) in 1694. These were mostly servants of rulers and governments.

But the really big twist came in 1914, when the U.S. Federal Reserve Bank was created. Its creation was mired with worries that it might socialize the economy.