Some authorities, relying upon a broad definition of banking that equates it with any sort of intermediation activity, trace banking as far back as ancient Mesopotamia, where temples, royal palaces, and some private houses served as storage facilities for valuable commodities such as grain, the ownership of which could be transferred by means of written receipts. There are records of loans by the temples of Babylon as early as 2000 bce; temples were considered especially safe depositories because, as they were sacred places watched over by gods, their contents were believed to be protected from theft. Companies of traders in ancient times provided banking services that were connected with the buying and selling of goods.

Many of these early “protobanks” dealt primarily in coin and bullion, much of their business being money changing and the supplying of foreign and domestic coin of the correct weight and fineness. Full-fledged banks did not emerge until medieval times, with the formation of organizations specializing in the depositing and lending of money and the creation of generally spendable IOUs that could serve in place of coins or other commodity moneys. In Europe so-called “merchant bankers” paralleled the development of banking by offering, for a consideration, to assist merchants in making distant payments, using bills of exchange instead of actual coin. The merchant banking business arose from the fact that many merchants traded internationally, holding assets at different points along trade routes. For a certain consideration, a merchant stood prepared to accept instructions to pay money to a named party through one of his agents elsewhere; the amount of the bill of exchange would be debited by his agent to the account of the merchant banker, who would also hope to make an additional profit from exchanging one currency against another. Because there was a possibility of loss, any profit or gain was not subject to the medieval ban on usury. There were, moreover, techniques for concealing a loan by making foreign exchange available at a distance but deferring payment for it so that the interest charge could be camouflaged as a fluctuation in the exchange rate.

The earliest genuine European banks, in contrast, dealt neither in goods nor in bills of exchange but in gold and silver coins and bullion, and they emerged in response to the risks involved in storing and transporting precious metal moneys and, often, in response to the deplorable quality of available coins, which created a demand for more reliable and uniform substitutes.

In continental Europe dealers in foreign coin, or “money changers,” were among the first to offer basic banking services, while in London money “scriveners” and goldsmiths played a similar role. Money scriveners were notaries who found themselves well positioned for bringing borrowers and lenders together, while goldsmiths began their transition to banking by keeping money and valuables in safe custody for their customers. Goldsmiths also dealt in bullion and foreign exchange, acquiring and sorting coin for profit. As a means of attracting coin for sorting, they were prepared to pay a rate of interest, and it was largely in this way that they eventually began to outcompete money scriveners as deposit bankers.

Banks in Europe from the 16th century onward could be divided into two classes: exchange banks and banks of deposit. The last were banks that, besides receiving deposits, made loans and thus associated themselves with the trade and industries of a country. The exchange banks included in former years institutions such as the Bank of Hamburg and the Bank of Amsterdam. These were established to deal with foreign exchange and to facilitate trade with other countries. The others—founded at very different dates—were established as, or early became, banks of deposit, such as the Bank of England, the Bank of Venice, the Bank of Sweden, the Bank of France, the Bank of Germany, and others. Important as exchange banks were in their day, the period of their activity had generally passed by the last half of the 19th century.

In one particularly notable respect, the business carried on by the exchange banks differed from banking as generally understood at the time. Exchange banks were established for the primary purpose of turning the values with which they were entrusted into bank money—that is, into a currency that merchants accepted immediately, with no need to test the value of the coin or the bullion given to them. The value the banks provided was equal to the value they received, with the only difference being the small amount charged to their customers for performing such transactions. No exchange bank had capital of its own, nor did it require any for the performance of its business.

In every case deposit banking at first involved little more than the receipt of coins for safekeeping or warehousing, for which service depositors were required to pay a fee. By early modern times this warehousing function had given way in most cases to genuine intermediation, with deposits becoming debt, as opposed to bailment (delivery in trust) contracts, and depositors sharing in bank interest earnings instead of paying fees. (See bailment.) Concurrent with this change was the development of bank money, which had begun with transfers of deposit credits by means of oral and later written instructions to bankers and also with the endorsement and assignment of written deposit receipts; each transaction presupposed legal acknowledgement of the fungible (interchangeable) status of deposited coins. Over time, deposit transfers by means of written instructions led directly to modern checks.

Although the Bank of England is usually credited with being the source of the Western world’s first widely circulated banknotes, the Stockholms Banco (Bank of Stockholm, founded in 1656 and the predecessor of the contemporary Bank of Sweden) is known to have issued banknotes several decades before the Bank of England’s establishment in 1694, and some authorities claim that notes issued by the Casa di San Giorgio (Bank of Genoa, established in 1407), although payable only to specific persons, were made to circulate by means of repeated endorsements. In Asia paper money has a still longer history, its first documented use having been in China during the 9th century, when “flying money,” a sort of draft or bill of exchange developed by merchants, was gradually transformed into government-issued fiat money. The 12th-century Tatar war caused the government to abuse this new financial instrument, and China thereby earned credit not merely for the world’s first paper money but also for the world’s first known episode of hyperinflation. Several more such episodes caused the Chinese government to cease issuing paper currency, leaving the matter to private bankers. By the late 19th century, China had developed a unique and, according to many accounts, successful bank money system, consisting of paper notes issued by unregulated local banks and redeemable in copper coin. Yet the system was undermined in the early 20th century, first by demands made by the government upon the banks and ultimately by the decision to centralize and nationalize China’s paper currency system.

The development of bank money increased bankers’ ability to extend credit by limiting occasions when their clients would feel the need to withdraw currency. The increasingly widespread use of bank money eventually allowed bankers to exploit the law of large numbers, whereby withdrawals would be offset by new deposits. Market competition, however, prevented banks from extending credit beyond reasonable means, and each bank set aside cash reserves, not merely to cover occasional coin withdrawals but also to settle interbank accounts. Bankers generally found it to be in their interest to receive, on deposit, checks drawn upon or notes issued by rivals in good standing; it became a standard practice for such notes or checks to be cleared (that is, returned to their sources) on a routine (usually daily) basis, where the net amounts due would be settled in coin or bullion. Starting in the late 18th century, bankers found that they could further economize on cash reserves by setting up clearinghouses in major cities to manage nonlocal bank money clearings and settlements, as doing so allowed further advantage to be taken of opportunities for “netting out” offsetting items, that is, offsetting gross credits with gross debits, leaving net dues alone to be settled with specie (coin money). Clearinghouses were the precursors to contemporary institutions such as clearing banks, automated clearinghouses, and the Bank for International Settlements. Other financial innovations, such as the development of bailment and bank money, created efficiencies in transactions that complemented the process of industrialization. In fact, many economists, starting with the Scottish philosopher Adam Smith, have attributed to banks a crucial role in promoting industrialization.