Which currency did Russia default on during the financial crisis of August 1998?

Russia defaulted on domestic ruble-denominated debt and devalued the Russian ruble during its August 1998 financial crisis.

Russia had accumulated substantial short-term obligations while receiving reduced tax revenues and facing weak commodity prices. The government struggled to maintain the ruble’s exchange-rate band and to refinance its debt. On August 17, 1998, it announced a devaluation, a temporary moratorium on some foreign debt payments, and a restructuring of domestic debt.

The crisis damaged Russian banks and businesses and pushed inflation higher. It also contributed to the collapse of Long-Term Capital Management, whose positions were threatened by extreme market volatility. The episode is sometimes described simply as a sovereign default, but the announcement combined debt restructuring, currency devaluation, and a banking crisis. The ruble was later redenominated in 1998, with 1,000 old rubles becoming one new ruble.