> Well for a start half those dead currencies were replaced with new currencies issued by a different authority and their holders compensated, often at parity.

> Well for a start half those dead currencies were replaced with new currencies issued by a different authority and their holders compensated, often at parity. Indeed, I see on that list the several Brazilian Cruzeiro/Cruzado currencies. The only difference between each of these and their predecessor is that three zeros were cut: if you had 1000 of the old currency, you had 1 of the new currency. The last of these was replaced by the current currency (Real) at a slightly different rate (2750 instead of 1000). That is, it was more like a renaming than the currency actually dying and being replaced. And there was no different authority in these cases, they were all issued by the same central bank.