The United Kingdom experienced the stock-market and currency crisis known as Black Wednesday on September 16, 1992. The day marked Britain’s forced withdrawal from the European Exchange Rate Mechanism, or ERM.
The British government had promised to keep the pound within a narrow band against other European currencies. Heavy selling pressure made that target increasingly difficult to defend. The government raised interest rates and spent foreign-exchange reserves, but those measures failed to stabilize sterling.
Black Wednesday is often described primarily as a currency crisis rather than a conventional stock-market crash. Its importance to financial markets came from the scale of the official intervention and the sudden abandonment of the exchange-rate commitment.
George Soros became famous for betting against the pound, but the episode involved many market participants and reflected wider economic and policy pressures. Britain’s exit later influenced debate about fixed exchange rates and the country’s relationship with European monetary integration.