The medieval period roughly stretched from the collapse of the Roman empire in the 5th century, to the start of the renaissance at the end of the 15th century. This period witnessed the rise and fall of several peoples. The Anglo-Saxon tribes came to dominated the island, and soon converted to Christianity by the 8th century. Their hold over the land was weakened by Danish vikings in the 9th century, who raided the coastlines for decades, before establishing a kingdom in the north. In 1066 the island was conquered by French Normans. The final centuries of the medieval period were defined by marked social change. The Normans introduced a new feudal farming system, the island’s population doubled in the 12th and 13th century, and the black death ravaged that number back down towards the end of the era. Finally, the war of the roses, a brutal civil war, raged across the nation. Henry VII’s emergence as victor from this conflict in 1485 is typically used to mark the end of the medieval era, and the start of the early modern period.