Quote Originally Posted by Mithradates
Couldnt everyone have a different currency name but the same value? Simply to make thing a little different.
But why?

The only case I can see for that is the Muslim factions, all the others used florins/bezants, which were made to the same standards, had names used interchangeably, and in many cases accounts might have had a mix of the two. (After all, precious metal coinage can remain in circulation for literally thousands of years.)