Which hedge fund's near-collapse became a major concern during the 1998 Russian financial crisis?

Long-Term Capital Management became a major concern during the 1998 Russian financial crisis.

LTCM was a highly leveraged hedge fund founded in 1994. It used quantitative trading strategies and positions in bonds, derivatives and other markets. After Russia defaulted on domestic ruble debt and devalued the ruble in August 1998, investors rapidly sought safer assets.

The resulting market turmoil caused losses on several of LTCM’s positions. Because the fund was deeply connected to major financial institutions, the Federal Reserve Bank of New York helped arrange a private-sector rescue in September 1998. The central bank did not directly provide the bailout money.

The episode demonstrated how leverage and interconnected derivatives could turn a fund’s losses into a wider financial-stability concern. LTCM’s rescue is often incorrectly described as a government bailout; the participating private banks supplied the capital, while the New York Fed coordinated the process.