"Castle" is a wide-ranging history of some of the most magnificent buildings in Britain. It explores many of the country's most famous and best-loved castles, as well as some little-known national treasures. The story begins in the 11th century, when castles were introduced to Britain, and ends in the 17th century, when they were largely abandoned. It is, in some respects, an epic tale, driven by characters like William the Conqueror, "Bad" King John and Edward I, who, by building and besieging castles, shaped the fate of the nation. At the same time, however, it is a more homely story, about the adventures, struggles and ambitions of lesser-known individuals, and how every aspect of their lives was wrapped up in the castles they built. As Marc Morris shows, there is more to castles than drawbridges and battlements, portcullises and arrow-loops. Be it ever so grand or ever so humble, a castle is first and foremost a home. It may look tough and defensible on the outside, but on the inside, a castle is all about luxury and creature comforts. Inside real castles, we do no necessarily find cannons and suits of armour, but we do discover great halls, huge kitchens, private chambers and chapels - all rooms which were once luxurious and lavish, and which made these buildings perfect residences for their owners. To understand castles - who built them, who lived in them, and why - is to understand the forces that shaped medieval Britain.