28 July 1914: War begins and markets start to break

Austria-Hungary declared war on Serbia, setting off the First World War. Investors across Europe rushed to sell securities and grab cash and gold, and exchanges began closing one after another as prices collapsed. Within days the panic reached New York. The war would reshape the global economy, wreck empires and move financial power from London toward New York. Few saw the scale coming on the first day.

The lesson: Geopolitical shocks can reshape the financial world for decades, far beyond the first panic.