This was a migration such as had never before been seen; bands of armed men, all young or in the prime of life, coming not as mere robbers, but seeking to conquer for themselves and to settle upon whatever land seemed to them most desirable. Everywhere they went they conquered and either exterminated or drove out the indigenous population, as in the south and east of England, or established themselves as an aristocracy, a ruling military caste, as the Franks in the north-east of Gaul. And everywhere they established firmly their individualistic social organisation, especially the isolated homestead of the individualistic family, characterised by the despotic power of the father and by great regard for individual property and for the rights of the individual as against all State institutions and public powers. In hostile countries the homestead became a fortified place, or at least was furnished with a fortified keep or castle; and in those regions, such as Gaul, in which the indigenous population was not exterminated, the feudal system was thus initiated. Everywhere they carried their spirit of independence, enterprise, and initiation. It was the swarming of the young broods of Northmen in search of new homes that caused the Romans to describe these Northern lands as the womb of peoples, and to regard them with wonder and something of fear. These qualities and habits continued to be displayed in the highest degree by the Normans after their first settlement in the north of France. The younger sons kept up the good old fashion of going out into the world to seek a fortune or rather a territory, which often was a dukedom or a kingdom. Their most characteristic performance was the conquest of the greater part of Italy. A little before William of Normandy and his companions secured for themselves domains in this country, Norman knights, engaging in enterprises that might well have seemed absolutely foolhardy, had established themselves in Mediterranean lands. Some two thousand Normans, arriving Viking fashion in their small ships, conquered Sicily and the south of Italy and divided these lands among themselves; and for a time they introduced order and a settled mode of life among the peoples of those parts. The leading spirits among them were ten sons of one Norman gentleman, Tancrède de Hauteville, the father of twelve sons of whom two only remained at home, while each of the others carved out for himself a domain in Italy. As Demolins remarks, these families, retaining undiminished their individualistic tendencies and spirit of independence, were veritable factories of men for exportation.