The Lydians
Situated between the Mediterranean, Aegean, and Black seas, the Lydians built their nation in Asia Minor. By around 600 B.C. they had developed a wealthy nation, which was known throughout the region for its rich supplies of Gold.
At this time surrounding nations still used a system of barter to exchange goods. A sack of grain for a set amount of cloth, and so forth. The Lydians introduced coins, and began the concept of trading goods for money.
The use of money quickly spread from Lydia into the surrounding civilizations.