Duchy of Courland in the political system of the Polish-Lithuanian Commonwealth (second half of the 16th century – end of the 17th century)

The article contains an analysis of the situation of the Duchy of Courland and Semigallia in the Polish-Lithuanian Commonwealth in military, political, socio-economic, religious and cultural terms. It is concluded that Courland’s vassalage from the Polish-Lithuanian state was moderate in character. The author proposes a periodization of the history of mutual relations between the socio-historical entities in question, focusing on the weakening of the influence of the dominant state up on the vassal state