 In the 19th and first half of the 20th centuries, they were found in large numbers, especially in the South Downs near Lewes.In 1813, Arthur Young estimated 200,000 ewes were kept on the eastern South Downs and commented, "the amazing number they keep is one of the most singular circumstances in the sheep husbandry of England".The principal reason for the large concentrations of Southdown sheep on downland farms over these centuries was their role in the maintenance of soil fertility.