1 The part of English law based on rules developed by the royal courts during the first three centuries after the Norman Conquest (1066) as a system applicable to the whole country, as opposed to local customs. The Normans did not attempt to make new law for the country or to impose French law on it; they were mainly concerned with establishing a strong central administration and safeguarding the royal revenues, and it was through machinery devised for these purposes that the common law developed. Royal representatives were sent on tours of the shires to check on the conduct of local affairs generally, and this involved their participating in the work of local courts. At the same time there split off from the body of advisers surrounding the king (the curia regis) the first permanent royal court – the Court of Exchequer, sitting at Westminster to hear disputes concerning the revenues. Under Henry II (reigned 1154–89), to whom the development of the common law is principally due, the royal representatives were sent out on a regular basis (their tours being known as circuits) and their functions began to be exclusively judicial. Known as justiciae errantes (wandering justices), they took over the work of the local courts. In the same period there appeared at Westminster a second permanent royal court, the Court of Common Pleas. These two steps mark the real origins of the common law. The judges of the Court of Common Pleas so successfully superimposed a single system on the multiplicity of local customs that, as early as the end of the 12th century, reference is found in court records to the custom of the kingdom. In this process they were joined by the judges of the Court of Exchequer, which began to exercise jurisdiction in many cases involving disputes between subjects rather than the royal revenues, and by those of a third royal court that gradually emerged – the Court of King's Bench (see Court of Queen's Bench). The common law was subsequently supplemented by equity, but it remained separately administered by the three courts of common law until they and the Court of Chancery (all of them sitting in Westminster Hall until rehoused in the Strand in 1872) were replaced by the High Court of Justice under the Judicature Acts 1873–75.
2 Rules of law developed by the courts as opposed to those created by statute.
3 A general system of law deriving exclusively from court decisions.