The 1929 Wall Street Crash began its major panic phase during October. The New York market suffered a severe sell-off on Black Thursday, 24 October, followed by Black Monday and Black Tuesday on 28 and 29 October.
The Dow Jones Industrial Average had reached a record closing high of 381.17 on 3 September 1929. By mid-November, it had lost almost half its value from that peak. The market continued to decline afterward and did not reach its ultimate low until July 1932.
October’s crash was connected to earlier speculation, widespread buying on margin, uneven economic growth, and weakening industrial conditions. It was not an instant one-day collapse, and the Great Depression had multiple causes beyond share prices. The month is sometimes confused with September 1929 because the market peak occurred then, but the defining panic sessions took place in October.