The main two lands later become Lithuania Minor, Nadruvia and Scalovia, had Prussian ethnic substratum. Lithuanian elements prevailed in the toponymy of the territory, though. It is possible that Nadruvia and Skalovia had changed ethnically in the process of Lithuanian penetration to and consolidation of the Baltic lands in the pre-state times. The contacts between Nadruvian and Scalovian populations with those to the north and west, where the grand dukes of Lithuania were ruling from the 13th or the 12th century, were probably close. Nadruvia had bordered on Sudovia and Samogitia, Skalovia – on Samogitia and Nadruvia. The inside Baltic migration, trading and ethnic consolidation presumably had happened since the earlier times than the German military invasion occurred.