Before World War I many Masurians emigrated to the Ruhr Area, especially to Gelsenkirchen. Here, Masurians were not distinguished apart from the Poles and both groups were seen as inferior to Germans, culturally or even racially. Despite those official efforts, German scholars usually considered Masurians as a group of Poles. In all German geographical atlases published at the beginning of the 20th century, the southern part of East Prussia was marked as an ethnically Polish area, with the number of Poles estimated at 300,000.