What event triggered the worldwide stock-market crash of March 2020?

The COVID-19 pandemic triggered the worldwide stock-market crash of March 2020.

As the virus spread internationally, governments imposed travel restrictions, business closures, and stay-at-home measures. Investors rapidly reassessed company earnings, economic activity, and credit risk. Major indexes fell into bear-market territory at exceptional speed.

The crash was intensified by an oil-price dispute between Saudi Arabia and Russia in early March. Energy shares suffered as oil prices fell, while uncertainty affected airlines, hospitality companies, banks, and many other industries. Central banks and governments then announced large monetary, fiscal, and public-health responses.

The 2020 crash is sometimes described as a single event, but it involved several sharp sessions. US trading was halted by circuit breakers on March 9, March 12, March 16, and March 18. The S&P 500 reached a closing low on March 23 before staging a rapid recovery, although economic damage and market effects continued.