Anything that is valuable, fungible and divisible could be used as money (you could even use barrels of oil). For examples, see [1]. Again, a great contemporary example is Bitcoin (not sure why you're ignoring that, it's a great example of money that exists in spite of government, not because of it).
Perhaps what you're referring to is legal tender, which indeed requires a government to exist. However, not all money is legal tender (for example, euros are not legal tender in the US, afaik).
Perhaps what you're referring to is legal tender, which indeed requires a government to exist. However, not all money is legal tender (for example, euros are not legal tender in the US, afaik).
1. https://en.wikipedia.org/wiki/Commodity_money