The 1720 British financial bubble centered on South American trade was the South Sea Bubble.
The South Sea Company received a government-backed monopoly over trade with Spanish South America in 1711, although the practical trading opportunities were far more limited than many investors imagined. In 1720, the company proposed taking over part of Britain’s government debt, and its shares rose dramatically as public excitement spread.
Investors bought shares on expectations of easy profits, while promoters encouraged speculation. Parliament also approved the Bubble Act, which restricted companies operating without a charter and intensified attention on the South Sea Company. When confidence broke, the share price collapsed, ruining many investors.
The episode is often discussed alongside France’s Mississippi Bubble and the Dutch tulip speculation, but these were separate events. The South Sea Bubble was not a modern stock-exchange crash in the same sense as 1929; it was an early example of a debt-linked speculative boom followed by a dramatic collapse.