Overview: Bettany Hughes considers the fourth age, between 410 and 1066 AD, a period of change that led to the disintegration of Britannia following the gradual collapse of the Roman Empire and an invasion by Scandinavians and northern Europeans, hungry for power and land. Out of the upheaval and chaos came the gradual development of a wealthy, independent England, which many would recognise today in areas of language, law, religion and economy.