ENThe former traditional Lithuanian proper names in the south of the Grand Duchy of Lithuania used to belong to one geographical unit spanning Voronovo, Lida, Grodno, Suwalki–Białystok and Lithuania Minor. However, the history of this area is very diverse. Various Baltic tribes lived there and belonged to different administrative units, not to one state. The aim of the article is to find the differences in stress, formation, pronunciation, motivation and contacts with other languages in the proper names of this area. The former proper names of the Grand Duchy of Lithuania and Prussian borders are now found in three states. The article examines 3,950 place names and personal names: 1) 900 (500 place names and 400 personal names) in current Belarus between Voronovo and Grodno; 2) 1,880 (1,170 oikonyms, microtoponyms, 110 hydronyms, 600 personal names) in present-day Poland; 3) 1,170 place names from Lithuania Minor in the area of Kaliningrad, now belonging to Russia. These proper names are described in more detail in the following sections, the forthcoming scientific monograph and its appendices. Keywords: traditional proper names, stress, formation, motivation, contacts. [From the publication]