Źródła do dziejów południowo-wschodnich Inflant (późniejszych Inflant polskich) w latach 1561–1600 w archiwach Rygi i Wilna

The purpose of this article is to present selected sources to the history of Latgale in the years 1561-1600, the earliest period of the membership of the former Livonia to the Polish-Lithuanian Commonwealth. Currently the records are stored in the archives and libraries of Riga, and Vilnius cities. Latgale, one of the major contemporary historical regions of Latvia, since the late 17th century was called the Polish Livonia, but within the borders of Poland stayed to 1772. The article discusses selected sources stored in the Latvian State Historical Archives (Latvijas Valsts vēstures arhīvs) in Riga and in the External Archives of the City Council of Riga (Rīgas Magistrate Arejais Arhīvs), as well as the National Library of Latvia (Latvijas Nacional Library). Characterized were also fonds stored in the Lithuanian State Historical Archives (Lietuvos Valstybės istorijos archyvas) in Vilnius and the former Wróblewski Library (Lietuvos mokslų akademijos Vrublevskių library) in Vilnius. Moreover, there was discussed the fate of public and private archives and libraries that had in their holdings sources to the history of Latgale in the last forty years of 16th century that within the 19th and first half of the 20th century were dispersed or destroyed. The attention was focused on the selected archives and libraries of Polish-Livonian nobility. Furthermore, there was discussed the holdings and fate of the Daugavpils municipal archives that was almost completely destroyed in the late 18th century.