The official name of the 1873 US financial panic that helped begin the Long Depression is the Panic of 1873.
The panic began in the United States after the failure of Jay Cooke & Company on September 18, 1873. Jay Cooke had been a major financier of railroad construction, and investors became alarmed about railroad overbuilding, excessive borrowing, and falling returns. The New York Stock Exchange closed temporarily on September 20.
The financial shock spread through the interconnected economies of Europe and North America. Bank failures, business closures, falling prices, and unemployment followed. In the United States, the downturn lasted for years and is commonly called the Long Depression, although terminology and dating differ among historians and countries.
The panic is sometimes incorrectly described as beginning solely with the Vienna stock-market crash earlier that year. The Vienna crash was a major European event and helped spread international financial stress, but the American panic has its own specific trigger and name.