What 1720 speculative collapse followed the failure of the South Sea Company in Britain?

The 1720 speculative collapse surrounding the South Sea Company in Britain was the South Sea Bubble.

The South Sea Company received a monopoly over British trade with parts of Spanish America, although its actual trading prospects were limited. In 1720, Parliament approved a plan allowing the company to convert large amounts of government debt into shares. Promotional claims and easy credit pushed the share price dramatically higher.

The boom attracted investors from many social classes and encouraged copycat ventures, including companies with little or no viable business. When confidence weakened, the South Sea share price fell sharply. Many investors were ruined, and the scandal caused a major political crisis involving company directors and public officials.

The South Sea Bubble is often discussed alongside the Mississippi Bubble in France because both collapses occurred in 1720. It was not a modern stock-market crash measured by an exchange index, but a famous early financial bubble and collapse.