Originally posted by Isator Levi
Anyway, I was talking about a specific period in which there was a transition away from it being a thing, and the related social implications, as pertained to the subject of what kinds of money would exist and why.
It depends on a bit on there being a market economy in which whomever is collecting from you can participate, or otherwise what their expenses are.
For example, in the satrapies, I could picture there being more money trickling up in the form of currency, because the people at the top need to regularly make tributes that include currency.
There's also an inversion of the concept, in which a government wants people to engage in certain kinds of labour, and so requires them to yield cash in order to push them towards that. I've heard that at a certain point in Chinese history, the authorities started demanding taxes in silver as a way of encouraging larger sections of the populace to devote their farming to silk production rather than food crops.
The Realm is pretty flexible in its demands of tribute, and a big part of a satrap's job is determining exactly what his satrapy is good for, and liasing with his Great House to figure out what to best leverage out of it. The standard of course is money, but due to the dizzying variety of cultures and societies the Realm extorts, that's not always practical. Sometimes it's useful or precious metals mined directly out of the satrapy by the natives and handed straight up to the Realm. Sometimes it's silk, spices, gems, drugs, or exotic plants. If nothing else, the Realm can simply demand slaves (they don't generally care where or how you get them). In other cases, the Realm has ended up in possession of a really 'useless' satrapy and forcibly converted the entire population into industrial production of some commodity it needs, such as lengths of chain, rope, helmets, shields, or whatever else is in constant demand somewhere within the boundaries of the empire. (The problem of pumping out X metric tons of socks for the legions and also growing enough food to survive the winter is left to the ingenuity of the natives to address.)