Which 1998 default and devaluation crisis caused a worldwide market shock after Russia stopped paying some debt?

The Russian financial crisis was the 1998 collapse involving Russia's debt default, ruble devaluation, and severe market disruption.

Russia faced falling tax revenues, weak commodity prices, heavy short-term borrowing, and political uncertainty. On August 17, 1998, the government and central bank announced a devaluation of the ruble, a restructuring of domestic debt, and a temporary moratorium on some foreign debt payments. The ruble then lost most of its value.

The crisis damaged Russian banks and investors and contributed to a global flight from risk. The collapse of Long-Term Capital Management in the United States soon afterward showed how international financial links could amplify a regional shock. Russia's economy eventually recovered, helped partly by higher oil prices and the cheaper ruble, but the 1998 episode remained a major post-Soviet financial turning point.