Which company's shares gave their name to Britain's 1720 stock bubble and crash?

The South Sea Company gave its name to Britain's 1720 stock bubble and crash, known as the South Sea Bubble.

Founded in 1711, the company was created to help manage Britain's national debt and was granted a monopoly over trade with Spanish South America. In practice, war and Spain's control of the region made profitable commerce unrealistic. The company instead became increasingly involved in converting government debt into company shares.

Promoters encouraged extravagant expectations about overseas trade, while politicians and insiders benefited from share dealings and questionable loans. The stock price rose from roughly £100 to about £1,000 in 1720 before collapsing later that year. Thousands of investors were ruined, and a parliamentary investigation exposed fraud and political corruption.

The South Sea Company is often confused with the Mississippi Company, whose similarly timed French collapse formed the Mississippi Bubble. The Bank of England and the East India Company were important financial institutions during the British crisis, but neither gave the episode its name. The South Sea Company itself survived in reorganized form for more than a century.