Which 1987 crash became the first major modern global stock-market crash?

Black Monday became the first major modern global stock-market crash in 1987.

Black Monday refers primarily to October 19, 1987, when markets around the world collapsed together. The Dow Jones Industrial Average fell 22.6%, while major markets in Hong Kong, London, Australia, and Canada also suffered exceptional losses. The synchronized decline demonstrated how electronic communications and increasingly integrated financial markets could transmit panic rapidly across borders.

The crash followed a long rise in share prices and occurred amid concerns about interest rates, exchange rates, trade imbalances, and slowing economic growth. Portfolio-insurance programs and computerized trading may have accelerated the fall by generating additional sell orders as prices declined.

The episode helped prompt reforms in market structure and risk management. Exchanges introduced circuit breakers, and central banks emphasized their willingness to provide liquidity during severe disruptions. Black Monday is distinct from Black Tuesday in 1929: the names sound similar, but they refer to different crashes separated by nearly six decades.