List of national legal systems
Common law is currently in practice in Ireland, most of the United Kingdom (England and Wales and Northern Ireland), Australia, New Zealand, Bangladesh, India (excluding Goa), Pakistan, South Africa, Canada (excluding Quebec), Hong Kong, the United States (on a state level excluding Louisiana), and many other places. In addition to these countries, several others have adapted the common law system into a mixed system. For example, Nigeria operates largely on a common law system, but incorporates religious law.
Law
Common law originated from England and has been inherited by almost every country once tied to the British Empire (except Malta, Scotland, the U.S. state of Louisiana, and the Canadian province of Quebec). In medieval England, the Norman conquest the law varied-shire-to-shire, based on disparate tribal customs. The concept of a "common law" developed during the reign of Henry II during the late 12th century, when Henry appointed judges that had authority to create an institutionalized and unified system of law "common" to the country. The next major step in the evolution of the common law came when King John was forced by his barons to sign a document limiting his authority to pass laws. This "great charter" or "Magna Carta" of 1215 also required that the King's entourage of judges hold their courts and judgments at "a certain place" rather than dispensing autocratic justice in unpredictable places about the country. A concentrated and elite group of judges acquired a dominant role in law-making under this system, and compared to its European counterparts the English judiciary became highly centralized. In 1297, for instance, while the highest court in France had fifty-one judges, the English Court of Common Pleas had five. This powerful and tight-knit judiciary gave rise to a systematized process of developing common law.