The Lydians were an ancient civilization that lived in what is now western Turkey. They are best known for their rich culture and contributions to trade, particularly through the use of coins. The Lydians are credited with creating one of the first known coins made from electrum, a natural alloy of gold and silver, which helped facilitate commerce and economic growth in the region. The most famous Lydian king was Croesus, who ruled in the 6th century BCE. His wealth became legendary, leading to the phrase "rich as Croesus." The Lydians also had a significant influence on neighboring cultures, including the Greeks, through trade and cultural exchange.