Which currency came under attack during the 1992 Black Wednesday market crisis?

The currency attacked during the 1992 Black Wednesday market crisis was pound sterling.

On September 16, 1992, Britain was forced to withdraw the pound from the European Exchange Rate Mechanism, commonly called the ERM. The system required participating currencies to stay within agreed bands against one another, but pressure from currency traders made Britain’s target increasingly difficult to defend.

The British government raised interest rates and announced further measures to support sterling, yet the pressure continued. The pound was eventually allowed to float, and it depreciated. The episode became a major political embarrassment for the government and damaged confidence in Britain’s ERM policy.

Black Wednesday is not the same event as the 1987 Black Monday stock-market crash. It was principally a currency and exchange-rate crisis, although it had major consequences for financial markets and economic policy.