What was the nickname of the 1720 collapse of the South Sea Company’s share price?

The 1720 collapse of the South Sea Company’s share price was called the South Sea Bubble.

The South Sea Company received a monopoly over British trade with Spanish South America, although its realistic trading opportunities were far more limited than many investors imagined. In 1720, the company proposed converting part of Britain’s government debt into shares, and enthusiasm drove its price to extraordinary heights.

The share price then collapsed later that year as confidence failed. Thousands of investors suffered losses, and the episode damaged public trust in joint-stock companies and financial promoters. Parliament investigated the affair, uncovering corruption and improper behavior among influential figures.

The South Sea Bubble is often discussed alongside the Mississippi Bubble in France, which also burst in 1720. They were separate schemes, not two names for one company. The episode is an early example of a speculative bubble involving expectations, leverage, government finance, and rapidly reversing crowd confidence.