As soon as this became known among the hungry Saxon tribes of northern Germany, they sailed across the North Sea and made themselves at home in the prosperous island. They founded a number of independent Anglo-Saxon kingdoms (so called after the original Angles or English and the Saxon invaders) but these small states were for ever quarrelling with each other and no King was strong enough to establish himself as the head of a united country. For more than five hundred years, Mercia and Northumbria and Wessex and Sussex and Kent and East Anglia, or whatever their names, were exposed to attacks from various Scandinavian pirates. Finally in the eleventh century, England, together with Norway and northern Germany became part of the large Danish Empire of Canute the Great and the last vestiges of independence disappeared.