It is characteristic of the post-Soviet historiography of Lithuania and many other post-Communist countries to ignore socio-economic history, which was important during the Soviet period. New theoretical approaches and “leading ideas” generating historiographic and empirical problems can serve to stimulate this type of research. One such approach is the neo-Marxist capitalist world system theory (CWS). The book provides different explanations in CWS theory and traditional Marxist historiography of socio-economic development in Central and Eastern Europe (especially in the Polish-Lithuanian Commonwealth (PLC)) in the 16th–18th centuries, a critical analysis of the two theories base assumptions and methodological oppositions and, based on this analysis and historical information, a determination of the nature of socio-economic relations dominating in the PLC in the 16th–18th centuries: either feudal serfdom or peripheral capitalism. This book is the first systematic attempt to consider the socio-economic history of the PLC in the 16th–18th centuries from the perspective of global history employing the conclusions of global discussions about this research subject.