Originally Posted by Ralph Sir Edward
The pistole was originally a Spanish denomination, also referred to as a double escudo, I believe. France and Spain did a lot of trade 1500's and 1600's, so France struck Louis D'Or to the Spanish standard, as well as maintaining their own local currency (livres), which could be exchanged back and forth. In the 1800's and early 1900's, some Latin American countries did the same with English pounds (gold) and French 20 Francs (gold). Peru made some very pretty trade coins...
also, little trivia for you, "la livre" means the pound in french (not to be confused with "le livre", the book), this name comes from a monetary system which was used by france until the revolution and
in... the UK, until 1971.
1 livre = 20 sous or 240 deniers, and 1 sou = 12 deniers