ENBased the archaeological data, historical sources, linguistics and toponymy, it is possible to determine five directions of Semigalian migration to Lithuania. First of all, approximately in 1284–1285 and later in 1298–1290 Semigallians migrated in two directions: neighbouring Šiauliai and Upytė lands. From Upytė they took the third direction along the Nevėžis River to the surrounding area of the present Kaunas. The fourth direction was through Šiauliai to the depth of contemporary Samogitia: surrounding lands of Viduklė, Nemakščiai, Skaudvilė, Kražiai, Medininkai, Ariogala. The fifth direction led to the East Lithuania: environs of Kernavė and Vilnius. According to historical and linguistics data, it was determined that migration to Livonia was based on three directions: Curonia (Kuldīga, Sabile and other areas), Vidzeme, Mitau. Semigallian migration to East Lithuania (Vilnius environs) necessitates reviewing theory of the third decade of the 20th century (1924) by K. Būga on Semigallian (or Pro-Semigallians) migration from East Lithuania (Vilnius environs) to the historical territory of Semigallia. In the fourth decade of the 20th century (1937), the theory was adopted by the Latvian historian Fr. Zālītis, and in the seventh decade of 20th century (1967), developed by Žeimelis region researcher J. Šliavas. Later this theory was demolished. Recent research studies urge to review this theory, which was disputable from the very beginning. It had evidence, however, the period and direction were mixed. Semigallians migrated not from Vilnius environs to historical Semigallia in the 6th century, but to the opposite, from East Lithuania, at the end of the 13th century.Due to thepassage of the Teutonic Knights crusades, lands most having suffered from depopulation are the West Žiemgala lands: Tērvete, Dobele, Žagarė, Silene (?), Sidabrė. Places which suffered less are Dobene, East Semigallia (Upmale) and the least impact was done to Plonė, which belonged to East Semigallia. Researchers indicate that the population of Semigallia in 11th and 12th century was approxi-mately 17–24 thousand. It is difficult to say how many dwellers and how many per cent of them could abandon their places of residence. It may be assumed that the number of dwellers who left their places of residence could reach more than a half. Usually migrants were settled in frontier regions, nonresidential areas. Semigallian migrants (the elite of society – noblemen, soldiery, craftsmen) were granted special rights (usually military functions); they settled in the most important defence centers of the Grand Duchy of Lithuania. Semigallian elite integrated naturally into social, economic and political structures of the Grand Duchy of Lithuania. A relatively high social organization of Semigallia made this integration more efficient than the remote relations with Sudovians, Scalovians and Nadrovians. Кey words: weapons, brooch, cemetery, hill-fort, land, Semigallians. [From the publication]