CURFEW, CURFEU or COUVRE-FEU, a signal, as by tolling a bell, to warn the inhabitants of a town to extinguish their fires or cover them up (hence the name) and retire to rest. This was a common practice throughout Europe during the middle ages, especially in cities taken in war. In the law Latin of those times it was termed ignitegium or pyritegium. In medieval Venice it was a regulation from which only the Barbers' Quarter was exempt, doubtless because they were also surgeons and their services might be needed during the night. The curfew originated in the fear of fire when most cities were built of timber. That it was a most useful and practical measure is obvious when it is remembered that the household fire was usually made in a hole in the middle of the floor, under an opening in the roof through which the smoke escaped. The custom is commonly said to have been introduced into England by William the Conqueror, who ordained, under severe penalties, that at the ringing of the curfewbell at eight o'clock in the evening all lights and fires should be extinguished. But as there is good reason to believe that the curfew-bell was rung each night at Carfax, Oxford (see Peshall, Hist, of Oxford), in the reign of Alfred the Great, it would seem that all William did was to enforce more strictly an existing regulation. The absolute prohibition of lights after the ringing of the curfew-bell was abolished by Henry I. in noo. The practice of tolling a bell at a fixed hour in the evening, still extant in many places, isa survival of the ancient curfew. The common hour was at first seven, and it was gradually advanced to eight, and in some places to nine o'clock. In Scotland ten was not an unusual hour. In early Roman times curfew may possibly have served a political purpose by obliging people to keep within doors, thus preventing treasonable nocturnal assemblies, and generally assisting in the preservation of law and order. The ringing of the " prayer-bell," as it is called, which is still practised in some Protestant countries, originated in that of the curfew-bell. In 1848 the curfew was still rung at Hastings, Sussex, from Michaelmas to Lady-Day, and this was the custom too at Wrexham, N. Wales.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)