In this introduction to the medieval history of the British Isles - England, Scotland, Ireland and Wales are viewed together, revealing the similarities and contrasts between the different regions. During the period 1100-1400 the British Isles formed a political sphere of great complexity, and were closely integrated with continental Europe. the most dynamic power was that represented by the Anglo-Norman aristocracy, church, and monarchy, and their successor, the Plantagenet state. Robin Frame traces the expansion of this power, which by 1300 had embraced the whole of Wales and much of Ireland. He examines how the Scottish kings alone sustained and extended a rival orbit, and how the prolonged clash between the two monarchies eventually loosened the control of each over its Gaelic fringes. The book covers a number of individual topics, including the aristocracy, kingship, government, border societies and the political communities that emerged on both sides of the Irish Sea by the late fourteenth century. Robin Frame is the author of Colonial Ireland 1169-1369 and English Lordship in Ireland 1318-1361