Which 1929 event began with Black Thursday on October 24 in the United States?

The 1929 event that began with Black Thursday on October 24 in the United States was the Wall Street Crash of 1929.

The crash followed years of rapidly rising share prices, widespread speculation, and stock purchases made with borrowed money. On October 24, 1929, panic selling produced enormous trading volume. Black Monday, October 28, and Black Tuesday, October 29, brought further collapses.

The crash did not single-handedly cause the Great Depression, but it sharply damaged confidence, wealth, and investment. Banks, businesses, and households were affected as falling asset prices combined with bank failures, reduced production, and unemployment. A common mix-up is treating the crash and the entire Great Depression as identical events: the crash was a major financial shock, while the Depression was a much broader economic crisis that lasted through the 1930s.