The writing revolution began 5,000 years ago with cuneiform writing. The first gold-silver system emerged under the Persians, followed by the Athenian tetradrachm as the early leading currency of the Mediterranean region. Rome minted the denarius, which led to inflation in times of war. In the Middle Ages, Louis the Pious reformed the coinage system and the Florentine fiorino stood for economic strength. Silver coins such as the Maria Theresa thaler became cross-border trading currencies. The French franc symbolized revolutionary ideas, while under George III, Great Britain modernized its currency - on the way to becoming the next global reserve currency.