There’s an excellent Radio 4 series (of ten 15 minute programmes) The History of Money.
I say excellent based on only two episodes 
and urge those interested in this thread to listen to today’s episode: The Classical Period (15 minutes long)
It contains some really interesting facts about debt, trade and money, including a really important one right at the end. Main ones from memory:
- money was not created to facilitate trade (a popular incorrect assumption), in fact some of the biggest trading nations were late to adopt it
- coinage was brought about in order to facilitate war and empire (that figures!) as a way to make, er incentivise, the nearby population to provide logistical resources to soldiers. This made it much more efficient to maintain armies all over the place
- before coinage, rulers dealt with debt burden problems by forgiving all debt periodically, after coinage this was not attractive, which meant the plebs became overburdened with debt unless other means were found to return wealth to them from the rich.
- similar philosophies appear to have arisen at different places due to the arrival of money, as well as anti-war movements, often religious, some interesting ones in China.
- if rulers did not forgive the debts of the masses, or have other ways that returned wealth to them, the rulers generally realised too late, and the civilisation collapsed. Oh dear!
Today’s repetition of the last scenario appears obvious, along with the futility of QE being used to further enrich or our ruling elite (bankers) rather than the populous. Oooh political!