What 2010 event saw European stock markets plunge after concerns about Greek sovereign debt?

The 2010 event in which European stock markets plunged amid concerns about Greek sovereign debt was the European sovereign-debt crisis.

Greece revealed that its public-finance statistics were worse than previously reported, intensifying fears about government debt sustainability. Investors demanded higher borrowing costs from several euro-area countries, and concern spread to Portugal, Ireland, Italy, and Spain.

Stock markets fell sharply in May 2010 as investors worried about defaults, banking exposure, and the stability of the euro area. European governments and international institutions created rescue programs and imposed policy conditions on countries receiving assistance.

The crisis was not the same as the global financial crisis that began in 2007–08, although the two were closely connected. Weak banks, recession, public debt, and the design of the euro area all contributed to the European episode.