The Corn Laws were tariffs and other trade restrictions on imported food and corn enforced in the United Kingdom between 1815 and 1846. The word corn in British English denoted all cereal grains, including wheat, oats and barley. The laws were designed to keep corn prices high to favour domestic producers, and represented British mercantilism. The Corn Laws blocked the import of cheap corn, initially by simply forbidding importation below a set price, and later by imposing steep import duties, making it too expensive to import it from abroad, even when food supplies were short. The House of Commons passed the corn law bill on 10 March 1815, the House of Lords on 20 March and the bill received royal assent on 23 March 1815.

Mercantilism is a nationalist economic policy that is designed to maximize the exports and minimize the imports for an economy. In other words, it seeks to maximize the accumulation of resources within the country and use those resources for one-sided trade.