John Law of Edinburgh was a gambler of genius — a calculator of odds who lived off the card tables of Europe — with a killing on his record (a duel over a lady, 1694), an escape from an English death cell, and, remarkably, one of the era’s sharpest monetary minds: his 1705 treatise argued that money was not silver but circulation, and that a nation short of coin could and should run on well-managed paper.
Bankrupt, war-drained Regency France was the desperate patient his theory needed. The Regent, Philippe d’Orléans — a fellow spirit who knew Law from the tables — let him found a note-issuing bank (1716), which became the state’s Banque Royale; then the Compagnie d’Occident (1717), holding the trade monopoly of Louisiana — a Mississippi wilderness sold to investors as an Eldorado of mines and willing commerce. Law absorbed the tobacco farm, the African and Indies companies, the mint, and the entire tax farm, until one conglomerate — and one man, made Controller-General of Finances — ran France’s money, taxes, colonies, and debt: shareholders would swap government bonds for Mississippi shares, and the national debt would simply become equity.
The rue Quincampoix
Through 1719 the machine ran on its own exhaust: the bank printed notes, the notes bought shares, the rising shares justified more notes. Stock climbed from 500 livres toward 10,000; the narrow rue Quincampoix became a howling open-air exchange where duchesses jostled lackeys, a hunchback reportedly rented his hump as a writing desk, and fortunes made overnight demanded a new word — millionnaire, a French coinage of 1719. Emigrants for Louisiana were harder to mint: the company swept prisons and streets for colonists, and chained brides shipped to Biloxi died in numbers the prospectus omitted.
In 1720 arithmetic resumed. Insiders cashed shares into gold; Law answered with force — banning bullion holdings, devaluing coin, finally decreeing shares and notes down by half in May 1720, which converted doubt into stampede. Runs on the bank crushed people to death at its doors; the shares fell to embers; and Law, burned in effigy, slipped abroad with almost nothing, dying in Venice in 1729 on a gambler’s income and a pauper’s estate. His system’s wreckage was audited for years in the Visa; France’s lasting takeaways were a generational horror of banks and paper money (the very word banque was avoided) — a fiscal rigidity that ran downhill toward 1789 — and the sale, in Napoleon’s time, of the Louisiana that had been the story’s collateral all along.
The same spring, across the Channel, the South Sea Bubble ran the same arc on the same debt-for-equity logic: 1720, the year Europe invented the modern financial crash, twice.