Which bank’s collapse is widely seen as the start of the 2008 global financial crisis?

Lehman Brothers’ collapse is widely seen as the start of the acute phase of the 2008 global financial crisis.

The investment bank filed for bankruptcy on September 15, 2008, after it could not find a buyer or obtain sufficient government support. With more than $600 billion in assets, it was the largest bankruptcy filing in U.S. history at that time. Its failure intensified fear about the solvency of banks and the safety of money-market and credit markets.

Lehman had accumulated major exposure to mortgage-related assets and commercial real estate. When U.S. housing prices fell and mortgage defaults increased, those assets became difficult to value and sell. The firm’s bankruptcy triggered widespread losses and contributed to a sharp freezing of interbank lending.

Bear Stearns had already required emergency assistance in March 2008, so it was an important earlier warning. Lehman’s failure, however, became the defining collapse of the crisis and preceded extraordinary government interventions around the world.