Peasant producers are now recognized as having played an important part in the late medieval economy: this can also be said of peasant producers in eastern England before the Conquest. In the wake of the Viking invasions Scandinavian settlers from the second half of the ninth century entered a region that was already commercially active. Independent farmers raised sheep, possibly a newly introduced breed, on the Lincolnshire Wolds and marketed their wool. A network of Anglo-Scandinavian shippers and traders, members of a merchant elite, controlled important places on river routes. That Lincolnshire was an area of light manorialization and many sokemen had an invigorating effect on its economy. Peasant producers had comparative freedom and by controlling markets and extracting cash from the inhabitants of their sokes Anglo-Norman lords profited from an economy that had been invigorated by Scandinavian enterprise.