Trade did not come to a halt, and interconnectedness between communities was still more prevalent. On the other hand, in the areas of central Europe most of the fighting between the barbarians and the Romans had taken place. It is there that the feudal and manorial systems develop most strongly. They spread up into England, though Around the fourth to sixth centuries there is a general movement away from free citizenship, particularly in the country, to what is technically known as serfdom. This is not the same as slavery.
Slavery is even lower.
But, serfdom meant that individuals were no longer free to leave their homes or communities. They were literally bound to the soil. At the same time they were protected by the ones who were stronger to whom they had given their allegiance. The manorial system then became the economic system. It also became in a sense the legal system of what would be called the non-noble or common class.