English law
Common law is a term with historical origins in the legal system of England. It denotes, in the first place, the judge-made law that developed from the early Middle Ages as described in a work published at the end of the 19th century, "The History of English Law before the Time of Edward I", in which Pollock and Maitland expanded the work of Coke (17th century) and Blackstone (18th century). Specifically, the law developed in England's Court of Common Pleas and other common law courts, which became also the law of the colonies settled initially under the crown of England or, later, of the United Kingdom, in North America and elsewhere; and this law as further developed after those courts in England were reorganised by the Supreme Court of Judicature Acts passed in the 1870s, and developed independently, in the legal systems of the United States and other jurisdictions, after their independence from the United Kingdom, before and after the 1870s. The term is used, in the second place, to denote the law developed by those courts, in the same periods (pre-colonial, colonial and post-colonial), as distinct from within the jurisdiction, or former jurisdiction, of other courts in England: the Court of Chancery, the ecclesiastical courts, and the Admiralty court.
Natural law
The concept of natural law was very important in the development of the English common law. In the struggles between Parliament and the monarch, Parliament often made reference to the Fundamental Laws of England, which were at times said to embody natural law principles since time immemorial and set limits on the power of the monarchy. According to William Blackstone, however, natural law might be useful in determining the content of the common law and in deciding cases of equity, but was not itself identical with the laws of England. Nonetheless, the implication of natural law in the common law tradition has meant that the great opponents of natural law and advocates of legal positivism, like Jeremy Bentham, have also been staunch critics of the common law.