German invasion. Prussian Lithuanian population The two main lands later became 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. The land probably depopulated during the war and the source of the regeneration of the population was internal as well as presumably mainly external from neighbouring areas. The land was resettled by returning refugees and newcomers from the Grand Duchy of Lithuania. After the permanent war had ended finally with the Treaty of Melno in 1422, the population continued to grow. The newcomers were Lithuanians from Trakai, Vilnius voideships and Samogitia. Lithuanian farmers used to flee to the Sudovian forest, which lain in the Trakai Voivodeship, and live here without dues, what was possible until the agrarian reform of Lithuania, performed during the second half of the 16th century. The tribal areas such as Nadruvia, Scalovia, Sudovia had to some extent later coincided with the political administrative and the ethnic areas. Nadruvia and Scalovia became Lithuanian Province in Prussia and the Yotvingian population persisted in their lands more commonly as western Lithuanians in the Grand Duchy of Lithuania and Prussia. Distribution As a distinctive ethno-cultural region, Lithuania Minor emerged during the 15th or the 16th century. The substratum of the Prussian Lithuanian population comprised mostly ethnic Baltic tribes – either local (Old Prussians – Sambians, north Bartians, Natangians; either probably formerly Lithuanized or Prussian Scalovians and Nadruvians; Sudovians, some Curonians) or from neighbouring areas (newcomers from the Grand Duchy of Lithuania: Lithuanians from the right side of the middle reaches of the Neman or Suvalkija, Samogitians, Sudovians, Prussians etc.). Colonists from the Holy Roman Empire also contributed to the Lithuanian population to some extent. Prussians and Yotvingians tended to be assimilated by Lithuanians in Lithuania Minor. Lithuanian percentage decreased to about half of population in about half