John Law’s System in France fused a note-issuing bank with a rising colonial trading company. In 1719–1720 paper notes and Mississippi Company shares inflated together. The bust of 1720 was a paper-and-shares collapse under a regency seeking relief from war debt. It is not the same episode as France’s later assignats, and it is not “France printed Weimar.”
Who John Law was
John Law (1671–1729) was a Scottish financier and monetary theorist. He argued that a well-managed paper currency, backed by sound assets and careful issue, could expand trade beyond the limits of scarce coin. After exile and travel on the Continent, he gained the ear of the French Regent, Philippe d’Orléans, in the years after Louis XIV’s death.
France faced heavy public debts from long wars. Tax revenues were strained. Coin was hoarded or exported when confidence slipped. Law offered a modern-sounding fix: a bank that issued notes, and a company that could absorb state debt while developing colonial trade, especially around the Mississippi basin and Louisiana.
Law wrote and spoke as a reformer of credit, not as a carnival promoter in the first telling. His early proposals stressed order, reserves, and trade. The historical record then shows how political need and market mania outran those restraints. He was not a cartoon printer of endless paper from day one. His System grew by stages—bank notes, company shares, debt conversion, and monopoly privileges—until the pieces locked together and then broke.
The bank and the Mississippi Company
In 1716 Law founded the Banque Générale. It was later reorganized as the Banque Royale when the crown took a closer grip. The bank issued notes payable in coin under stated rules. Those notes circulated as a convenient claim on metal, not as metal itself.
Alongside the bank stood the company later known as the Mississippi Company—first the Compagnie d’Occident, then the Compagnie des Indes after mergers with other trading privileges. It held rights over colonial trade and related monopolies. The state used the company to refinance debt. Creditors were steered into shares instead of older claims on the treasury.
Bank and company became partners in one System. Notes supported share demand. Share enthusiasm supported confidence in notes. Offices, privileges, and propaganda tied the story of colonial wealth to the paper that funded it.
Keep the instruments distinct. A bank note was a promise to pay in coin, subject to the bank’s rules and reserves. A share was ownership in the company, priced in the market and fed by dividends, privileges, and speculation. Law’s danger was fusion. When the same political machine pushed both, a rise in shares felt like proof that notes were sound—and plentiful notes made shares easier to bid up.
How the Mississippi Bubble inflated
Through 1719 the company’s privileges widened. Debt-conversion schemes pulled more rentiers into shares. Share prices rose with extraordinary speed. New issues and subscriptions absorbed paper wealth that had nowhere else to go under the Regent’s policy mix.
Note issue expanded as the System tried to keep credit easy and share markets firm. For a time, paper seemed to create prosperity. Luxury spending rose in Paris. Speculators crowded the rue Quincampoix. Foreign visitors described a city obsessed with subscriptions and price talk.
Metal moved the wrong way for a durable note system. Coin and bullion were drawn into the whirl, then increasingly driven out as people preferred to hold or export hard money while spending the paper. When confidence is high, notes displace coin in daily use. When confidence cracks, coin leaves circulation or leaves the country. The note becomes only a claim on a thinning reserve. Law’s System leaned on confidence longer than on metal.
The peak of Mississippi share mania sits in late 1719 and early 1720. Prices that had multiplied then struggled to find new buyers at the top. Attempts to manage the market—controls on coin, forced relations between notes and shares, and shifting decrees—signaled strain rather than mastery. Peak and bust belong to that narrow window: mania cresting around the turn into 1720, collapse unfolding across 1720 as policy patches failed.
The collapse of 1720
In 1720 the System broke. Share prices fell from their peak. Bank notes lost credibility as convertibility and coin rules shifted under emergency decrees. Holders who could fled into metal and foreign exchange. Shops and markets relearned to distrust paper that had been mandatory or privileged only weeks before.
Law’s political protection evaporated as losses spread through the rentier class and the court. He left France. The Regency was left with ruined paper fortunes and a long memory of “paper systems.” Later French politics would invent new paper under new names. The 1720 scar remained part of public caution.
The bust was fast in market time. What had inflated as a joint note-and-share machine deflated as both legs failed together. The Banque Royale’s paper could not be defended once the company’s equity story died and coin fled.
Do not merge this episode with the French assignats of the 1790s. Assignats were revolutionary paper tied to confiscated church and émigré lands, issued decades later under a different regime and war finance. Do not merge it with Germany’s 1923 hyperinflation either. Weimar was a twentieth-century collapse of a national paper mark after war, reparations, and extreme monetization—one cautionary parallel among many, not the same event or the same century.
John Law’s 1720 leaves a narrower documentary lesson. Fusing a note-issuing bank with a rising equity story can inflate both until metal drains and confidence snaps. The Mississippi Bubble was paper-and-shares under Regency debt politics. It was not Weimar, and it was not the assignats.