King Croesus was the last king of Lydia, a kingdom in western Asia Minor, known for its immense wealth. He ruled from 595 to 546 BCE and is often associated with the saying "rich as Croesus," highlighting his legendary riches. His wealth came from the abundant natural resources of Lydia, particularly gold from the river Pactolus. Croesus is also famous for his interactions with the Greek oracle at Delphi, where he sought advice on whether to wage war against Persia. His story serves as a cautionary tale about the fleeting nature of wealth and the importance of wisdom in leadership.