At least the Roman Empire never devalued (inflated) its currency. As far as I know.
One of the last acts of the Roman Empire was to make huge numbers of non-Romans into citizens, that was the death knell
“At least the Roman Empire never devalued (inflated) its currency”
Yes, they did:
“Upon his accession Commodus devalued the Roman currency. He reduced the weight of the denarius from 96 per Roman pound to 105 (3.85 grams to 3.35 grams). He also reduced the silver purity from 79 percent to 76 percent – the silver weight dropping from 2.57 grams to 2.34 grams. In 186 he further reduced the purity and silver weight to 74 percent and 2.22 grams respectively, being 108 to the Roman pound.[2] His reduction of the denarius during his rule was the largest since the empire’s first devaluation during Nero’s reign.”
http://en.wikipedia.org/wiki/Commodus