The oil-related event that helped trigger the 1973–1974 stock-market crash was the 1973 oil crisis.
In October 1973, Arab members of OAPEC announced an oil embargo against countries seen as supporting Israel during the Yom Kippur War. Oil prices rose sharply, creating inflationary pressure and raising costs for transport, manufacturing, and households.
The shock arrived alongside slower economic growth, high inflation, and monetary tightening. Stock markets in the United States, the United Kingdom, and other countries fell heavily during 1973 and 1974, while many economies experienced the difficult combination later called stagflation.
The 1973 oil crisis was not the only cause of the market decline. It intensified existing economic weaknesses and changed expectations about energy prices and profitability. The event is distinct from the second oil shock of 1979, which followed the Iranian Revolution.