What was the name of the 1720 French speculative-market collapse associated with John Law?

The 1720 French speculative-market collapse associated with John Law was the Mississippi Bubble.

John Law, a Scottish financier, helped establish a company with a monopoly over French trade in the Mississippi region. The company became closely tied to a broad monetary and banking experiment in France, and investors bought its shares in enormous numbers as prices surged.

The boom depended heavily on confidence, easy money, and expectations about the wealth of French Louisiana. Those expectations were far greater than the company’s realized commercial returns. When investors began demanding cash and selling shares, the price collapsed, producing major losses and a crisis of confidence.

The Mississippi Bubble is often discussed alongside Britain’s South Sea Bubble, which also burst in 1720. The two episodes are related but distinct: the Mississippi Bubble centered on France and John Law’s financial system, while the South Sea Bubble centered on a British company and government debt arrangements.