The credit and debt system began before the written word. Approximately 9,000 years ago man invented counting tokens to keep track of trades and obligations. In fact, the art of writing was invented to record our financial dealings.
While the early counting tokens may have been a form of money, we don’t know for sure how they were used. It’s not until man developed a written language that we have our first complete financial records.
Before the days of the first recorded contracts and financial transactions, people used cattle, grain, silver or anything else they could agree on as currency to be used in a trade.
Over 3,000 years ago in the city of Uruk, people kept tabs on who owed what to whom on clay tablets like the one shown. These tablets contain the earliest-known recordings of financial transactions and were discovered in the area known as Mesopotamia.
Uruk was situated south of Baghdad, on an ancient branch of the Euphrates River, in Iraq (known in the Bible as Erech). Today the area is known as Warka.
These early writings appear to be contracts and fiscal records. It could be argued that writing was invented to keep track of these types of deals.
Map of Modern Iraq