In the history of late feudal Poland of the XV-XVIII centuries. A special role is played by the problem of its relations and contacts with the Baltic Sea. It is one of the most significant, because these contacts had a huge impact on the formation of economic, social, political relations, as well as the culture of the Polish-Lithuanian Commonwealth and its relations with the European world. It also significantly influenced the formation of the foreign policy of the medieval Polish state in relation to its northern (Scandinavian), as well as eastern neighbors (Livonia, the Grand Duchy of Moscow, and later tsarist Russia). Therefore, it has long been a subject of intense interest in Polish historiography and the science of neighboring countries, and the results of research conducted in People's Poland allow us to shed more light on this problem .1The role of Poland on the Baltic Sea in the 16th century was particularly fully elucidated, both due to the rich material of sources and taking into account the growing importance of maritime affairs in the internal and foreign policy of the Polish-Lithuanian Commonwealth. The purpose of this article is to summarize the key points of Poland's connection with the Baltic Sea during this period, as well as the main characteristic features of these contacts. The solid foundation of Poland on the Baltic Sea, at the mouth of its most important river artery-the Vistula-took place already in the middle of the XV century. It was then that the growing economic ties of the central Polish lands with Gdansk, the main port center of Privislinsky Pomerania, which was wrested from the Polish state by the German Order in 1308-1309, were revealed. The Order also held sway in Privislinska Torun, in the ancient Polish Helminsk land, and in Elblong, located in the Prussian lands it conquered. These large commercial cities maintained lively economic contacts with Polish lands and cities. This economic attraction to the mouth of the Vistula River o ... Read more