Keep

[keep]

A keep is a strong central tower which is used as a dungeon or a fortress. Often, the keep is the most defended area of a castle, and as such may form the main habitation area, or contain important stores such as the armoury, food, and the main water well, which would ensure survival during a siege.

An earlier word for a keep, still used for some medieval monuments, especially in France, is donjon; a derivative word is dungeon. In Germany, this type of structure commonly is referred to as a bergfried.

Development

Keeps exist in a remarkable variety of shapes and sizes. They may be of 'square' variety, generally found on the British Isles, cylindrical, octagonal, both regular and irregular polygonal forms, or a combination or several of these features. Effectively, some castles in fact, were no more than a keep and often these are referred to simply as tower houses.

Often early keeps were just square towers with very thick walls, scarcely more than a residential hall, such as Château de Langeais. This structure later developed into the more recognizable rectangular residential keep by the eleventh century.

The form and function of the keep changed with time and varied depending upon the region where it was built. As the keep was a defensive structure, the shaping trend changed to adapt to the developments in weapon technology. For example, the round or cylindrical keep was first introduced as a defense against the battering ram. A battering ram could cause severe damage to a side of a square tower, but merely would glance off the side of a rounded one. Also, a round tower is much harder to undermine successfully than a square one. Rounded towers also have the advantage of less "dead ground", or, areas not visible from the tower summit.

By the early twelfth century, cylindrical keeps had become popular and they remained prominent in France until the end of the medieval period (e.g. Montlhéry, Rouen). Variations on the rounded type began to appear at the same time. These included towers with triangular, prow-like projections (such as Château-Gaillard), polygonal keeps such as at Orford, or "multi-lobed" keeps such as Clifford's Tower.

From the early thirteenth century onward many castles were designed without traditional keeps, instead the preferred plans for defensive structures were concentrated in the walls and towers of the enceinte, or in a gatehouse. Early examples may be seen at Château de Boulogne-sur-Mer, in Boulogne-sur-Mer and Bolingbroke Castle in Bolingbroke, Lincolnshire, and later, at The Bastille. In some castles the gatehouse took over the functions of the keep, serving as refuge, residence, and command post, such as at Harlech Castle.

As nobles became more interested in grand halls and comfortable living quarters, the keep lost its domestic role. Although keeps continued to be used and built, there is evidence that many had a reduced role, demonstrated by the lack of residential amenities in the tower plans, such as latrines and chimneys.

In Western Europe, however, the defensible residential keep experienced a resurgence before the end of the medieval period, as towers were built to house nobles and their retinues securely, but at a very high level of comfort and luxury (e.g. Raglan Castle, Ashby de la Zouch Castle, Château de Vincennes, and Château de Largoët). This luxurious type was particularly popular in late medieval Scotland up until the 1600s (e.g. Craigievar Castle). Another word for this type of keep is the tower house.

Notable types

Norman or Romanesque keep

An archetypical form for the keep in the British Isles is the Norman keep, so-called because they were built throughout England and Ireland by Norman nobles. Norman keeps usually have several distinguishing features in common and the type was very popular during the eleventh and twelfth centuries. Most have towers at each corner, which usually extend above the main keep to form watchtowers. In many cases spiral staircases were contained in or near these corner towers. Another common feature was the forebuilding, which contained the entryway to the keep, its most vulnerable point. This structure extended from the side of the keep and often, was approached by stairs, as the entryway usually was above ground level. Sometimes a drawbridge guarded the top of the stairs. Inside, there usually is a central dividing wall that divides the interior in two parts. The living quarters for the noble or castellan of the castle were usually at the top of the keep, the great hall or halls were below the keep, and storage rooms were at the bottom of the structure. Keeps on this general plan may be seen throughout England and Ireland, with many examples in France as well, where they are known by the names donjon carré (a square keep) or donjon roman (a romanesque keep). Examples include the Tower of London and Rochester Castle in England and, Domfront and Loches in France.

Shell-keep

A unique form of keep is the shell keep which essentially, is a masonry 'fossilization' of a palisade lining the top of a castle defensive mound or motte. In a shell keep a strong wall was built around the top of the motte, and the domestic buildings were built against it, leaving a round courtyard in the middle. These differ from most keeps in that they are not a tower, but a defensive enclosure, although their purpose as a last refuge, as well as living quarters, is similar to other keeps. Good examples are Restormel Castle in Cornwall and Gisors Castle in Normandy.

Famous keeps

One of the most famous keeps in Europe is the White Tower of the Tower of London, constructed by William the Conqueror in the aftermath of the Norman Conquest.

The cylindrical donjon of Rouen, shown above, is all that remains of the large city fortress where Joan of Arc was imprisoned during her trial for heresy.

Shown to the right is the tallest keep remaining in existence, the donjon of Château de Vincennes, which is located in a suburb of contemporary Paris. Previously this distinction was held by the donjon of Coucy in Picardy.