Such was the method of construction of the simplest form of this type, of which Bures Mount in Essex, The Mount, Caerleon, and Clifford's Castle, Northamptonshire, are examples; but it is extremely questionable even if these cited cases were made without an accompanying bailey, although no traces can now be discerned. The accommodation would be so extremely limited, and the danger of starvation to the garrison so imminent, seeing that no room could be afforded for any cattle or sheep upon the motte, that, unless intended to be of a temporary nature or hastily raised in an emergency, we are justified in assuming that these forts, of which not very many occur, are in an incomplete condition.
Clifford's Castle, at Little Houghton, three miles east of Northampton, is an example of the Motte and Fosse; it is one of those defending the valley of the river Nen—Earl's Barton and Wollaston being similar companion defences. The hill is of large circumference, presenting imposing proportions, and may be compared with important works like those at Ongar and Pleshey in Essex, or with Thetford in Norfolk. It rises to a height of over 50 feet above its surroundings, and lies upon part of a small natural ridge. A ditch surrounds the base, the ballast from which was taken to the top of the hill in order to increase the height; the summit there, however, is level. In order to increase the efficiency of the fosse it was converted into a moat, water being admitted from the adjacent river. At the present time no traces whatever of a bailey are discernible, nor of any enclosure with masonry walls. This does not prove that these additions have never existed; the natural place for them would be upon the eastern side where high ground is situated, and if they have been built at any period they would present features similar to those at Thurnham in Kent. The summit of the mound would in that case be reached by a flying bridge of wood.
The Bailey, or base court, was an enclosed piece of land lying at the foot of the motte; a ditch surrounded it, the ballast from which was thrown up inside the area so as to make a rampart for palisading. The two ends of the ditch joined the fosse encircling the motte, generally upon opposite sides of the latter. In the bailey the buildings for the garrison, stables, offices and domestic buildings were erected, while the bretasche afforded accommodation for the lord of the castle, his family, and immediate attendants. In those cases where a second bailey occurs it is generally extended beyond the first on the face remote from the motte, as at Ongar Castle, Essex; but sometimes, though more rarely, both baileys will abut upon the mound, as at Newton in Montgomeryshire, while in a limited group of castles, including Windsor and Arundel, the motte occupies the centre of the whole defence.
It is not difficult to understand the almost universal rule that the mound is placed upon the outer edge of the enceinte; it was without doubt the strongest part of the position, and the refuge to which the besieged retreated when the bailey, or baileys, had been lost, and in the last extremity it afforded a means for escaping to the open country. This disposition of the mound with regard to the bailey should be borne in mind when dealing with those castles which have been erected in later times upon a pre-existing Motte and Bailey fortress, the mound, as a rule, with its accompanying enclosures serving as a nucleus around which masonry defences could be grouped.
Through the agency of the plough, and aerial forces of degradation of various kinds, baileys present but scanty traces at the present day in many instances, and this may be taken as proof, if any were needed, that earth and wood were the only kinds of material employed during the early Norman period in the construction of forts. No traces of stone have been discovered which can be assigned to that period with absolute certainty, and not only does this well-established fact corroborate the assertion, but documentary evidence points in the same direction.
It is quite possible that other Motte and Bailey castles besides the few enumerated may eventually be ascribed to the fifteen or twenty years preceding the Norman invasion, for there was nothing to prevent a wealthy Thegn from erecting one of this type which he may have observed on the Continent where many scores were in existence. The Bayeaux tapestry shows Dinant as being defended by a Motte and Bailey castle; the usual wooden tower is seen upon the top of the mound, and the enclosed bailey is stockaded. It also shows the construction of such a castle at Hastings, besides four similar examples in Brittany and Normandy.
Certain it is that almost immediately after 1066 a rapid construction of these fortified posts occurred in many parts of England and Wales, not necessarily equally distributed, but more thickly dotted in those places which the military instinct of the great Conqueror led him to deem desirable. Thus the Welsh borderland is remarkably rich in examples, Herefordshire alone containing thirty-two, as compared with Leicestershire four, Nottinghamshire five, and Hertfordshire four. It is remarkable, however, that many highly developed examples of this class are to be found in the eastern counties where no borderland existed, and we can only account for this anomaly by supposing that a Norman lord, to whom a grant of land had been assigned in recognition of his military services, hastened to consolidate his occupancy by the erection of a castle, and that such building might possibly not have any reference to the defence of the kingdom as a whole.
Thus the castle became the accredited centre of a feudal barony, and a Motte and Bailey in almost every case is connected with places mentioned in the Domesday Book as being the residence of a Norman landowner. For example, Berkhampstead, owned by Robert Count of Mortaign, boasts one of the most perfect specimens to be found in the country; the manors of Nigel de Albini at Cainhoe in Bedfordshire, Robert de Malet at Eye in Suffolk, William Fitz-Ansculf at Dudley in Staffordshire, Geoffrey Alselin at Laxton in Nottinghamshire, William de Mohun at Dunster in Somersetshire, Robert le Marmion at Tamworth in Staffordshire, Robert Todenei at Belvoir in Leicestershire, Henry de Ferrers at Tutbury in Staffordshire, Roger de Busli of Tickhill in the West Riding, and Ilbert de Lacy at Pontefract in Yorkshire, all exhibit the same feature.
These castles in many cases became the centre around which sprang up the dwellings of traders and agriculturists which subsequently developed into boroughs, while in not a few instances ecclesiastical settlements occurred which finally expanded into stately monasteries.
Again, many barons threw up castles in the centre of, or adjacent to, pre-existing towns, the subsequent fortifications of which became an integral part of the whole scheme of defence, as at Warwick, Nottingham, and Leicester. Wherever a castle was built for the double purpose of overawing a town and defending it against a common enemy, it is generally found placed upon the city defences or immediately adjacent thereto; and as the settlement had invariably originally sprung up in the vicinity of, or upon the banks of, a river, the fort is usually found placed at the junction where the borough and the river defences meet. A fortress situated in this position would be able to afford material help to a relieving army, while at the same time in the event of the town being captured and given to the flames it would occupy the best possible position, short of being entirely outside the walls, for the garrison to escape the effects of the conflagration. This position of the castle with respect to the town walls and other defences will be recognised in the cases of Warwick, Hereford, Stamford, Cambridge, Bedford, Chester, Shrewsbury, etc.