In 1800, just after Napoleon Bonaparte (1769–1821) had come to power in France, he appointed a commission of legal experts to consolidate all French civil law into one code. The process took four years; the so-called Code Civil went into effect on March 21, 1804, the same year that Napoleon named himself emperor of France (which he did in December), The laws thus took on the alternate name of the Code Napoleon or Napoleonic Code. It went into force throughout France, Belgium, Luxembourg, and in other French territories and duchies in Europe.

The code represented a compromise between Roman law and common (or customary) law. Further, it accommodated some of the radical reforms of the French Revolution (1789–99). The Code Civil set forth laws regarding individual liberty, tenure of property, order of inheritance, mortgages, and contracts. It had broad influence in Europe as well as in Latin America, where civil law is prevalent. As opposed to the common law of most English-speaking countries, civil law judgments are based on codified principles, rather than on legal precedent. For example, under the Code Civil an accused person is guilty until proven innocent (as opposed to common law, which holds that a person is innocent until proven guilty).