Frederick used propaganda to justify the partition and his economic exploitation of Poland, portraying the acquired provinces as underdeveloped and in need of improvement by Prussian rule; these claims were sometimes accepted by subsequent German historiography and can still be found in modern works. Frederick did not justify his conquests on an ethnic basis, however, unlike later nationalist, 19th-century German historians. Dismissive of contemporary German culture, Frederick instead pursued an imperialist policy, acting on the security interests of his state. Frederick II settled 300,000 colonists in territories he had conquered, and enforced Germanization.