From the dawn of civilization, credit has been the invisible engine of human progress and a source of profound social tension. This sweeping history traces the evolution of debt and lending, beginning not with money, but with the systems of trust and obligation that bound ancient societies together. Journey back to Mesopotamia, where the first interest-bearing loans were recorded on clay tablets, and to classical Greece and Rome, where sophisticated maritime loans financed vast trading empires. Explore how the great religions grappled with the ethics of usury, a debate that shaped economic life for centuries and spurred innovations from the warrior-monks of the Knights Templar to the powerful merchant bankers of Renaissance Italy who funded an artistic and cultural rebirth. The narrative follows the money into the modern age, revealing how credit financed the Age of Discovery and how the creation of national debt and the first central banks gave rise to the modern state. Witness the birth of consumerism in the 18th century, the credit-fueled innovations of the Industrial Revolution, and the financial chaos of the American colonies that led to Alexander Hamilton's visionary financial system. The book details the explosion of consumer credit in the Roaring Twenties, as the automobile and the installment plan reshaped American life, and the devastating collapse of that system into the Great Depression. It then chronicles the post-war boom, built on government-backed mortgages and the GI Bill, that created the American suburbs. Finally, this history brings us to the present day, charting the rise of the ubiquitous credit card from the exclusive Diners' Club to the global networks of Visa and MasterCard. It demystifies the complex financial engineering of the late 20th century, from the junk bonds that fueled the corporate raiders of the 1980s to the securitization and subprime mortgages that culminated in the 2008 global financial crisis. The story concludes with a look at the ongoing digital disruption, exploring how the FICO score, FinTech startups, peer-to-peer lending, and the radical new worlds of cryptocurrency and social credit systems are once again redefining the fundamental human relationship of trust and debt.