Essay from the year 2025 in the subject Economics - International Economic Relations, language: English, abstract: World War I significantly contributed to the rise of the US dollar as a key global currency. Before the war, the British pound sterling was the dominant international currency, serving as the main reserve currency and medium of exchange worldwide. However, the devastation caused by WWI led to economic instability in Europe, especially in Britain and France, which reduced confidence in their currencies. Meanwhile, the US economy experienced rapid growth during the war, becoming a major lender and supplier of goods to wartime allies in Europe. This shift increased global reliance on the US dollar as countries and investors held more reserves in dollars due to the size and stability of the US economy, and its dynamic financial markets. Although the London Monetary and Economic Conference of 1933 impacted negatively on the dollar strength, the Bretton Woods Agreement of 1944 officially established the US dollar as the world's primary reserve currency, linked to gold. This privileged status of the dollar endowed the United States with quite unique economic advantages-such as the ability to borrow cheaply, repay its international debts with its own currency and exert outsized influence on international finance and geopolitics. Yet the dollar's supremacy has never gone unchallenged. For nearly a century, policymakers, economists, and political leaders across the world have questioned the sustainability and fairness of a system so heavily reliant on one nation's currency. This book traces that long and complex story, from the early visionary ideas of John Maynard Keynes in the 1930s, through the postwar Bretton Woods system and the related Triffin's Dilemma, to contemporary challenges posed by regional currencies, such as the euro, digital innovations, like for instance the bitcoin, and emerging economic powers - in particular the enlarging BRICS.