Japan’s 1987 stock-market crash was known as Black Monday. On 19 October 1987, stock markets around the world fell dramatically, and Japan’s Nikkei 225 also suffered a major decline amid a global selling wave.
The crash began in the United States, where the Dow Jones Industrial Average dropped 22.6 percent in a single session. International markets quickly followed because financial markets had become increasingly connected through investment flows, trading systems, and currency relationships.
Japan’s economy was still in an enormous asset-price boom in 1987, with the Nikkei later reaching its historic peak in December 1989. Black Monday is therefore distinct from Japan’s later long decline after the early-1990s bubble burst. The name usually refers to the worldwide 19 October event, not a uniquely Japanese crash.