What was the 1720 collapse of shares in the British South Sea Company called?

The 1720 collapse of shares in the British South Sea Company was called the South Sea Bubble.

The South Sea Company received a government-backed monopoly over trade with parts of Spanish South America, although its realistic trading prospects were limited. Investors became excited by promotional claims and by a scheme that converted government debt into company shares.

Shares rose dramatically during 1720, attracting wealthy investors and members of the British political establishment. As confidence weakened, selling accelerated, and the price collapsed before the end of that year.

The South Sea Bubble was part of a wider speculative episode that also included the Mississippi Bubble in France. The scandal damaged public trust, led to investigations, and produced financial losses for investors. It is remembered as an early example of a market bubble driven by speculation, promotion, and unrealistic expectations.