The role of castles in the structuring of lordship is clear. From the first, we can see the main castles of the lordships being built in stone. The very fact of building in stone involved great resources, of both materials and men. Some of the latter must have been brought over to Ireland, because there was simply no tradition of designing such works there. Skilled masons had built churches in Ireland before, and we see them at work, making decorated features in Irish style, at Adare or Nenagh, but that is different from the overall planning of a castle. The programme of castle building must have joined that of the new church foundations of the new lords to give a major boost to the building
Industry. Both gave notice of the newcomers’ commitment to their new lands, and their intention to stay and transform them.
They chose stone not for defence but for prestige and utility. These castles were there to provide the administrative headquarters of their lords in their lordships and it shows in their designs. This was not to be simply the exercise of the old Irish system under new masters but a new form of lordship. For this a hall was essential, to administer the formal justice of the English and to provide a suitable setting for the social organisation of lordship, meeting tenants or allies among other lords. The separation of this public side of castle life from the private one of the lord’s chamber shows how the new men were determined to lead lives of at least as much pomp as their contemporaries. The extent of the accommodation provided for those not of the lord’s immediate household, at Trim or Carlingford, shows clearly how the new regime meant new types of administration, with elaborate staffs of officials. The spirit of display was also expressed in military means, as witnessed by the show of mural towers, and gate towers at Trim, Dunamase or Carlingford, with their parallels outside Ireland.
The proliferation of castles, with the widespread building of lesser, earthwork castles, was part of the same new lordship. The building of the many lesser castles followed the organisation of the land into a hierarchy of tenancies and estates with fixed centres of power. The castles were of earth and timber, not because they were earlier than the major stone castles, but because they could be erected quickly and cheaply. This is where the question of the extent of castle building under the earlier Irish kings becomes crucial. If it had been widespread, then we would have good evidence that the land was organised into territorial lordships. Instead, the new castles of the Irish of the twelfth century seem to be the work of kings, part of the increase of royal military power of the period.
The final point to be made is that, from the beginning, there is a great variety among the castles. This is apparent not only between the individual castles, but also between types and between lordships. At any period there will be large castles, built with great expenditure of resources, and smaller ones. The earthwork castles were not earlier than stone ones, nor were they exclusively built for men with smaller purses: some were built by great magnates, but at their lesser centres. It was not only a matter of fashion and resources but also the intended use of the castle which dictated its form. Within a group of castles built by men of similar status, are differences of emphasis, for example on military or domestic aspects. It is also likely that the parallels which we can see were apparent then also, that the sources and quotations of the design were meant to convey messages to contemporaries as well. Finally, the variations between lordships, which we can see in the deployment of early castles, is not unique to the period. All these are aspects of castles which we will see in later times.