Legal English the history of the development of English as a legal language. In prehistoric Britain, traditional common law was discussed in the vernacular (see Celtic law). The legal language and legal tradition changed with waves of conquerors over the following centuries. Roman Britain (after the conquest beginning in AD 43) followed Roman legal tradition, and its legal language was Latin. Following the Roman departure from Britain circa 410 and the Anglo-Saxon invasion of Britain, the dominant tradition was instead Anglo-Saxon law, which was discussed in the Germanic vernacular (Anglo-Saxon, Old English), and written in Old English since circa 600, beginning with
Anglo-Norman language a century after it had become the language of the king and of most of the English nobility. During the 12th century, development of the administrative and judicial institutions took place. Because the king and the lawyers at the time normally used French, it also became the language of these institutions. From the 12th century until the 15th century, the courts used three languages: Latin for writing, French as the main oral language during trials, and English in less formal exchanges between the judge, the lawyer, the complainant or the witnesses. The judge gave his sentence orally in Norman, which