Legal history or the history of law is the study of how law has evolved and why it has changed. Legal history is closely connected to the development of civilisations and operates in the wider context of social history. Certain jurists and historians of legal process have seen legal history as the recording of the evolution of laws and the technical explanation of how these laws have evolved with the view of better understanding the origins of various legal concepts; some consider legal history a branch of intellectual history. Twentieth-century historians viewed legal history in a more contextualised manner – more in line with the thinking of social historians. They have looked at legal institutions as complex systems of rules, players and symbols and have seen these elements interact with society to change, adapt, resist or promote certain aspects of civil society. Such legal historians have tended to analyse case histories from the parameters of social-science inquiry, using statistical methods, analysing class distinctions among litigants, petitioners and other players in various legal processes. By analyzing case outcomes, transaction costs, and numbers of settled cases, they have begun an analysis of legal institutions, practices, procedures and briefs that gives a more complex picture of law and society than the study of jurisprudence, case law and civil codes can achieve.

Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior, with its precise definition a matter of longstanding debate. It has been variously described as a science and as the art of justice. State-enforced laws can be made by a group legislature or by a single legislator, resulting in statutes; by the executive through decrees and regulations; or established by judges through precedent, usually in common law jurisdictions. Private individuals may create legally binding contracts, including arbitration agreements that adopt alternative ways of resolving disputes to standard court litigation. The creation of laws themselves may be influenced by a constitution, written or tacit, and the rights encoded therein. The law shapes politics, economics, history and society in various ways and also serves as a mediator of relations between people.