The urgency of the problem under study is conditioned by the tendency of the events reconsideration from the 15th - early 16th centuries outlined in the historical science, caused by the changes in the economic, political and social-cultural spheres, in the theoretical and methodological methods of research. The problem is also conditioned by the staying in the shadow concerning the issue of the Grand Duchy of Lithuania relations with the splinters of the Golden Horde, especially concerning the political contacts with the Kazan Khanate, which played a significant role in the struggle for political supremacy in the post-Horde space. The purpose of the article is to clarify the nature and the characteristics of the relationship of the Grand Duchy of Lithuania with two heirs of the Golden Horde - the Kazan and Crimean Khanates. The leading approach to the study of this problem is the comparative method. The study of the interstate relations of the Grand Duchy of Lithuania with the adjacent Crimean one and territorially removed from the principality by the Kazan yurts showed the existence of differences in the political line of Lithuania concerning the mentioned Tatar khanates and made it possible to find out the reasons for this. Two factors influenced the nature and the forms of studied state interrelations: 1) the presence or the absence of common borders; 2) the need to take into account the relationship between the post-Horde states and Lithuania with the Great Horde, the Ottoman Port and the strengthened Russian state. The diplomatic activity of the latter sometimes led to the change in the nature of interstate relations, conditioning the conversion of relations from diplomatic to military form, or the cessation of a military conflict, or a break of mutual contacts. The materials of the article can be used to reconstruct the general picture of state relations development in Eastern Europe during the period under review, as well as in the academic courses of lectures on general and Russian history.
