ENThe first half of the 17th century was the time of the Radziwiłł domination in the Grand Duchy of Lithuania. The towns of Bogusławpol and Januszpol, which were to become important craft and trade centers, were settled in the estates of their cousins Bogusław and Janusz on the border of the 1630s and 1640s. When the towns were founded, there was a period of wars and uprisings, which led to their collapse. With the deaths of Janusz (1655) and Bogusław (1669) the Protestant line of the Radziwiłłs broke, and Bogusławpol and Januszpol lost their names. Keywords: Grand Duchy of Lithuania, Radziwills, memorialization, city, town. [From the publication]