Medieval society in Europe was characterized by a clearly defined social stratification, which is best viewed as consisting of more or less closed communities united by similar political and power structure, conditions of life and hierarchies. The structure and evolution of medieval societies was influenced by a wide range of political, economic, social and cultural factors, often determined by rulers or other secular and ecclesiastical holders of power. One of the secondary objectives of this journal issue is to describe the structure of medieval societies in East-Central European monarchies and dominions and the investigation of coexistence, interaction and confrontation between different categories of the population. These topics still hold research potential due to a lack of recent studies on medieval society, which would re-evaluate older nationally or in other way biased perspectives within the context of contemporary East-Central European medieval studies. When researching the development, changes, disappearance and emergence of new legal/social categories of people and communities in medieval society in the future, it will be necessary to take into account a broader historical scope, spanning from the 9th to the 13th century.