Fortified house in the context of "Medieval castle"

A castle is a type of fortified structure built during the Middle Ages predominantly by the nobility or royalty and by military orders. Scholars usually consider a castle to be the private fortified residence of a lord or noble. This is distinct from a mansion, palace, and villa, whose main purpose was exclusively for pleasance and are not primarily fortresses but may be fortified. Use of the term has varied over time and, sometimes, has also been applied to structures such as hill forts and 19th- and 20th-century homes built to resemble castles. Over the Middle Ages, when genuine castles were built, they took on a great many forms with many different features, although some, such as curtain walls, arrowslits, and portcullises, were commonplace.

European-style castles originated in the 9th and 10th centuries after the fall of the Carolingian Empire, which resulted in its territory being divided among individual lords and princes. These nobles built castles to control the area immediately surrounding them and they were both offensive and defensive structures: they provided a base from which raids could be launched as well as offering protection from enemies. Although their military origins are often emphasised in castle studies, the structures also served as centres of administration and symbols of power. Urban castles were used to control the local populace and important travel routes, and rural castles were often situated near features that were integral to life in the community, such as mills, fertile land, or a water source.

A mansion is a large dwelling house. The word itself derives through Old French from the Latin word mansio "dwelling", an abstract noun derived from the verb manere "to dwell". The English word manse originally defined a property large enough for the parish priest to maintain himself, but a mansion is usually no longer self-sustaining in this way (compare a Roman or medieval villa). Manor comes from the same root—territorial holdings granted to a lord who would "remain" there.Following the fall of Rome, the practice of building unfortified villas ceased. Today, the oldest inhabited mansions around the world usually began their existence as fortified houses in the Middle Ages. As social conditions slowly changed and stabilized fortifications were able to be reduced, and over the centuries gave way to comfort. It became fashionable and possible for homes to be beautiful rather than grim and forbidding allowing for the development of the modern mansion.

In British English, a mansion block refers to a block of flats or apartments designed for the appearance of grandeur. In many parts of Asia, including Hong Kong and Japan, the word mansion also refers to a block of apartments. In modern Japan, a "manshon" (Japanese: マンション), stemming from the English word "mansion", is used to refer to a multi-unit apartment complex or condominium.

Bagenal's Castle (Irish: Caisleán Bagenal) is a 16th century fortified house located in Newry, County Down, Northern Ireland. It was rediscovered in 1996, where it was found located in the premises of the former McCann's Bakery. The castle consists of a rectangular plan with three storeys and was made with granite. During its restoration, sandstone was used as the replacement material.

A manor house was historically the main residence of the lord of the manor. The house formed the administrative centre of a manor in the European feudal system; within its great hall were usually held the lord's manorial courts, communal meals with manorial tenants and great banquets. The term is today loosely (though erroneously) applied to various English country houses, mostly at the smaller end of the spectrum, sometimes dating from the Late Middle Ages, which currently or formerly house the landed gentry.

Manor houses were sometimes fortified, albeit not as fortified as castles, but this was often more for show than for defence. They existed in most European countries where feudalism was present.