Back to the list of technologies
- "Wealth consists not in having great possessions, but in having few wants."
– Epictetus
- "Money, if it does not bring you happiness, will at least help you be miserable in comfort."
– Helen Gurley Brown
Currency is a Classical Era technology in Civilization VI. It can be hurried by making a Trade Route.
Strategy[]
The invention of a common trade medium is the first true economic advancement of mankind. The civilization with a currency sees a veritable ocean of new possibilities opening before it, and will need an entirely new District - the Commercial Hub, to explore these possibilities. The first building of this district, the Market, is also unlocked.
Currency, along with Horseback Riding, is another very important gateway tech in the early Classical Era. It unlocks the central-upper part of the tech tree, which is more economically-oriented than the lower part. Not only that, but it unlocks a crucial infrastructure for a nation's economical development - the Commercial Hub district. And if your civilization is landlocked, this district is the only way to increase your trading routes! But even more importantly, the Hub means considerable increase in 
Gold income, and if your civ's starting Luxuries (and their Improvements) weren't of the kind providing Gold, you will sorely need it to prevent early bankruptcy!
Unfortunately, It's not that easy to beeline Currency: you need to start with the upper-central part of the tree: Pottery -> Writing -> Currency, which isn't a particularly common research sequence. Chances are you will need other Ancient Era techs first, which will delay your research, so you'll have to make a choice: unlock important infrastructure to improve Luxuries and/or unlock military advancements, but delay boosting your raw Gold income; or beeline for Currency to gain Gold, but forego unlocking important infrastructure and military tech (which could leave you vulnerable to even the lowly Barbarians!).
Civilopedia entry[]
Currency, where something relatively worthless in itself represents some amount of actual value, has been the bane of civilization since around 2000 BC, when a form of receipt was used to show ownership of stored grain in temples in Sumer. The Egyptians soon adopted the practice for their own grain warehouses, so that individuals could claim a portion they had “banked” therein. Then small bits of rare metals, a lot easier to keep track of than written receipts (especially since these were on clay tablets), came to represent certain amounts of various commodities, able to be exchanged … or hoarded. Thus, wealth was determined by how many of these bits a person had.
But the collapse of the Mesopotamian and Mediterranean trading economy around 1100 BC revealed a flaw in this concept of circulating currency – it was only as good as the guarantees of worth that backed it. It was only with the recovery of Phoenician trade across the Mediterranean that coinage made a reappearance, this time being backed by rulers of the city-states of Phoenicia and Greece. Most of the major economies of the time were soon minting coins, usually out of gold or silver or copper. Trade flourished, taxes could be paid, banking evolved, and now people could even go into debt (a whole new concept).
It was left to the Chinese to “invent” paper currency, initially in the form of promissory notes from wholesaler’s shops backed by the merchant, but these were only useful in the local region. The Song dynasty began issuing a more universal paper currency based on the state monopoly of salt production. It took until the 13th Century for this paper money to finally become standardized and acceptable across the kingdom. Around the same time, the Islamic nations adopted the practice and established a stable, high-value currency (the dinar). A vibrant and vigorous monetary economy resulted; the Muslims thus were the first to have credit, cheques, savings accounts, trusts, exchange rates, and all the other wonders of a “modern” economy.
