00.0 – 00.57
An introduction to the series by the presenter, medieval historian Marc Morris. He outlines the main historical themes of the series, some of the castles that are featured and their central role in medieval history.
00.58 – 03.02
Marc takes us to Dover Castle and explains the link between the first castles in Britain and the invasion of the Normans.
03.03 – 09.59
The start of castle building in the 11th century is explored. The presenter explains the significance of the Vikings in Britain and France, and how this influenced the style of defensive structures in both countries. The Bayeux Tapestry is used as evidence of early castle-building techniques and styles.
10.00 – 12.57
We learn why the Normans constructed motte-and-bailey castles and why defence was so important. This type of castle was closely linked to the Norman's use of cavalry as a major defence mechanism.
12.58 – 21.59
An outline of the Norman invasion of Britain and how William the Conqueror became King of England. It includes a brief summary of the Battle of Hastings in 1066 and how William used castle-building to ensure his successful capture of the throne.
22.00 – 26.12
We discover that the first years of William's reign were anything but peaceful. He responded to major rebellions by the Anglo Saxons by building defensive castles all over the country. We learn about the 1069 York rebellion – in which thousands of men successfully attacked York Castle – and William's subsequent response, which culminated in the horrendous 'Harrying of the North'.
26.13 – 36.15
Marc describes the mass castle-building programme that took place over the next 20 years. William gave huge chunks of land to his friends for them to rule over. In particular, we hear the story of Roger of Montgomery, to illustrate how the lords ruled their lands and demonstrate the structure of the motte-and-bailey castles they built. We look in detail at how Hen Domen, one such castle on the Welsh-English border, would have been constructed.
36.16 – 39.37
Various sources of evidence are used to try to work out how many castles might have been built in this period, including the famous Domesday Book, the oldest surviving public record.
39.38 – 48.15
A summary of William's achievements and a preview of the stone castles that were slowly to replace wooden motte-and-bailey castles. The most important of all of these was The Tower of London – a mighty stone keep completed in 1087.

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