I know this is a lousy source, but my Latin teacher in High School claimed that Caesar invented fiat currency (although she didn't use those words). He put is

I know this is a lousy source, but my Latin teacher in High School claimed that Caesar invented fiat currency (although she didn't use those words). He put is face on gold coin, gave it to soldiers, and demanded that his taxes be paid not in any-old-gold, but in Caesar-face gold. Thereby ensuring that recently conquered villages have an incentive to feed and house the solders that conquered them. This way, those soldiers didn't need to resupply before moving on to the next village. It would seem that we've been using money to override ethics on behalf of the powerful ever since.