Battlement
A battlement, in defensive architecture, such as that of city walls or castles, comprises a parapet, in which gaps or indentations, which are often rectangular, occur at intervals to allow for the launch of arrows or other projectiles from within the defences. These gaps are termed embrasures, also called crenels or crenelles, and a wall or building with them is described as ; alternative older terms are and. The act of adding crenels to a previously unbroken parapet is termed crenellation.
The function of battlements in war is to protect the defenders by giving them part of the parapet to hide behind, from which they can quickly expose themselves to launch projectiles, then retreat behind the parapet. A defensive building might be designed and built with battlements, or a manor house might be fortified by adding battlements, where no parapet previously existed, or cutting crenellations into its existing parapet wall. A distinctive feature of late medieval English church architecture is to crenellate the tops of church towers, and often the tops of lower walls. These are essentially decorative rather than functional, as are many examples on secular buildings.
The solid widths between the crenels are called merlons. Battlements on walls have protected walkways, termed chemin de ronde behind them. On tower or building tops, the often flat roof is used as a protected fighting platform.
Etymology
The term originated in about the 14th century from the Old French word batailler, "to fortify with batailles". The word crenel derives from the ancient French cren, Latin crena, meaning a notch, mortice or other gap cut out often to receive another element or fixing; see also crenation. The modern French word for crenel is créneau, also used to describe a gap of any kind, for example a parking space at the side of the road between two cars, interval between groups of marching troops or a timeslot in a broadcast.Licence to crenellate
In medieval England and Wales a licence to crenellate granted the holder permission to fortify their property. Such licences were granted by the king, and by the rulers of the counties palatine within their jurisdictions, e.g. by the Bishops of Durham and the Earls of Chester and after 1351 by the Dukes of Lancaster. The castles in England vastly outnumbered the licences to crenellate. Royal pardons were obtainable on the payment of an arbitrarily-determined fine by a person who had fortified without licence. The surviving records of such licences, generally issued by letters patent, provide valuable evidence for the dating of ancient buildings. A list of licences issued by the English Crown between the 12th and the 16th centuries was compiled by Turner & Parker and expanded and corrected by Philip Davis and published in The Castle Studies Group Journal.There has been academic debate over the purpose of licensing. The view of military-focused historians is that licensing restricted the number of fortifications that could be used against a royal army. The modern view, proposed notably by Charles Coulson, is that battlements became an architectural status-symbol much sought after by the socially ambitious, in Coulson's words: "Licences to crenellate were mainly symbolic representations of lordly status: castellation was the architectural expression of noble rank". They indicated to the observer that the grantee had obtained "royal recognition, acknowledgment and compliment". They could, however, provide a basic deterrent against wandering bands of thieves, and it is suggested that the function of battlements was comparable to the modern practice of householders fitting highly visible CC
TV and burglar alarms, often merely dummies. The crown usually did not charge for the granting of such licences, but occasionally charged a fee of about half a mark.