The late medieval period is recognised as crucial in the development of the British Isles. During this period European society as a whole survived an assault of serious dimensions, in which dramatic changes (population collapse and economic upheaval) struck at the basis of the power of the lords who had dominated for centuries, often to the benefit of lesser lords. It was a period when, in Scotland and Ireland in particular, the power of the Kings was severely eroded. Tower houses were typically the buildings of lesser lords and gentry of Scotland, of northern England and Ireland. In these areas they are very common, with thousands surviving, and by their ubiquity, tower houses thus have a great deal to tell us about the period, in particular, about the fortunes and the patterns of life of the minor aristocracy who seem to have prospered more than the holders of great estates and the divergence of experiences in the British Isles. Small Castles in the British Isles provides, for the first time, a cohesive account of the small castles of Britain in the 14th to 16th centuries and shows how these castles relate to and add to an account of this important period.