The 1992 British currency crisis is known as Black Wednesday, when Britain withdrew the pound sterling from the European Exchange Rate Mechanism.
On September 16, 1992, the British government tried to defend the pound's ERM exchange-rate target by raising interest rates and buying sterling. Speculators continued selling the currency, judging that the target was unsustainable. The government eventually suspended the pound's ERM membership.
The episode damaged the Conservative government of John Major and became a major political embarrassment. It also showed how difficult it could be for a country to maintain a fixed exchange rate while facing market pressure and domestic economic constraints.
Black Wednesday was a currency crisis rather than a single stock-market crash. It is sometimes confused with Black Monday or Black Tuesday, names associated with major stock-market sell-offs.