Corn Laws
The British grain tariffs that kept bread expensive until 1846, when repeal split the Conservative party and turned Britain into a free-trade economy.
Corn in British usage means grain, mostly wheat. The Corn Laws were tariffs that kept foreign grain out of Britain in order to hold up the price of bread, and the thirty-year fight to repeal them was the first time a great power argued in public about whether trade policy should serve producers or consumers. Britain chose consumers in 1846, split its governing party doing it, and spent the next eighty years as the most open economy in the world.
The 1815 Importation Act was the sharpest version. Parliament, dominated by landowners, banned imports of foreign wheat outright until the domestic price reached 80 shillings a quarter, which was a very high bar. The effect was exactly as designed. Rents stayed high, landlords stayed rich, and bread stayed expensive.
Landlords against factories
The opposition came out of the new industrial cities. Manufacturers had an obvious complaint: expensive bread meant paying higher wages just to keep workers fed, which made British goods dearer abroad. They had a better second argument. If foreigners could not sell Britain grain, they could not earn the money to buy British cloth. Protection at home was destroying markets overseas.
The Anti-Corn Law League was founded in Manchester in 1838 and run by Richard Cobden and John Bright. It invented much of modern political campaigning: full-time paid lecturers, mass pamphleting through the new penny post, its own newspaper, and an operation that bought supporters the small property holdings they needed to qualify as voters. It also framed the issue as a moral one, the aristocracy taxing the food of the poor, which put the landlords on the wrong side of an argument about hunger.
The man who repealed the Corn Laws was not Cobden. It was Robert Peel, the Conservative prime minister and leader of the party the landowners controlled. Peel had been drifting toward free trade for years, and the potato blight that hit Ireland in 1845 forced the question. Repeal passed in 1846 with Whig and Radical votes against most of his own party. Benjamin Disraeli made his career attacking him for it. Peel's government fell within weeks and the Conservatives were shut out of stable power for a generation.
Repeal did not save Ireland. The famine killed around a million people, and the reasons lie in relief policy and land tenure rather than tariffs. Peel used the famine as an argument. He did not solve it.
What Britain became
After 1846 Britain stuck to open trade with unusual consistency, keeping it even as Germany and the United States industrialized behind tariff walls. It got cheap food, a huge export sector, and a career as the world's banker and shipper. By 1914 it was importing roughly four-fifths of its wheat.
That is also how Britain acquired a permanent vulnerability. A country that eats imported food has to control the sea lanes, which is one reason it maintained the largest navy on earth, and why German submarines came closer to winning both world wars by sinking merchant ships than the German fleet ever came by fighting warships.
The pattern the Corn Laws set has not gone away. Trade policy is rarely a fight between countries. It is a fight inside a country, between the people who gain from cheaper imports and the people whose livelihood the imports destroy, and a government has to choose which of them to disappoint. Every argument since, over American tariffs, European farm subsidies, or Chinese steel, is a rerun with different products.