 As a result, the territory was again sacked and devastated by Prussian raids, which led to depopulation of the province.Being involved in dynastic struggles elsewhere and too weak to deal with the Prussians alone, Conrad needed to safeguard and establish borders against the heathen Old Prussians, because his territory of Masovia was also in danger after the Prussians besieged Płock.Conrad awarded the already devastated Chełmno Land to the Teutonic Knights, giving them Nieszawa at first.