The courts of assize, or assizes (əˈsaɪzɪz), were periodic courts held around England and Wales until 1972, when together with the quarter sessions they were abolished by the Courts Act 1971 and replaced by a single permanent Crown Court. The assizes exercised both civil and criminal jurisdiction, though most of their work was on the criminal side. The assizes heard the most serious cases, most notably those subject to capital punishment or later life imprisonment. Other serious cases were dealt with by the quarter sessions (local county courts held four times per year), while the more minor offences were dealt with summarily by justices of the peace in petty sessions (also known as magistrates' courts).
The word assize refers to the sittings or sessions (Old French assises) of the judges, known as "justices of assize", who were judges who travelled across the seven circuits of England and Wales on commissions of "oyer and terminer", setting up court and summoning juries at the various assize towns.
Middle English assise < Old French assise ("session, legal action" – past participle of asseoir, "to seat") < Vulgar Latin *assedēre < Latin assidēre ("to sit beside, aside, elsewhere") < ad + sedēre ("to sit"). The “courts of assize” were the English equivalent of the still existing French « Cours d'assise ».
By the Assize of Clarendon of 1166 King Henry II established trial by jury by a grand assize of twelve knights in land disputes, and itinerant justices to set up county courts. Before Magna Carta was passed (enacted) in 1215, writs of assize had to be tried at Westminster or await trial at the septennial circuit of justices in eyre. The great charter provided for land disputes to be tried by annual assizes at more convenient places. This work soon expanded, becoming five commissions. In 1293, a statute was enacted which formally defined four assize circuits.