Abstract
<jats:p>The article is devoted to the problems of the functioning of the Sejm of the Grand Duchy of Lithuania in the 1530s. The features of the functioning of the Sejm of the Grand Duchy of Lithuania in this period are revealed using the example of the activities of the Hospodar’s ambassador Ivan Hornostay. The author showed the specific practice in the parliamentarism of the Grand Duchy of Lithuania in the 1500– 1530s, when Sigismund the Old was absent from the state, and his «presence» at the Sejm’s sessions was ensured by the Hospodar’s ambassadors. In the 1530s, the functions of the Hospodar’s ambassador were performed by Ivan Hornostay. The article showed the gradual development of Ivan Hornostay’s political career in the Grand Duchy of Lithuania, in which three stages were distinguished. The functionality of Ivan Hornostay as the Hospodar’s ambassador was also revealed. His competence included establishing communications between the monarch and the Sejm of the Grand Duchy of Lithuania, with the help of which Sigismund the Old exercised his powers within the framework of organizing the defense and finances, relations with the Moscow State and the Crimean Khanate.</jats:p>