This article analyses the transformation in the mode of partnership formation in seven countries of Eastern Europe. The aim of the study is to provide an up-to-date account of the switch from direct marriage to non-marital cohabitation as it has progressed from the 1960s to the mid-2000s, using data from the Generations and Gender Surveys. Unlike previous studies, we examined the extent to which cross-national variations in the onset and scale of transformation characteristic of the Second Demographic Transition, could be linked to nuptiality regimes that existed in the region in the 19th and early 20th centuries. With few exceptions, the results support the notion of correspondence between historical and contemporary patterns. Forerunners in the transition to partnership formation outside marriage tend to come from areas which exhibited a late/low prevalence of marriage; the latecomers are typically situated east of the Hajnal line. The article discusses plausible mechanisms underpinning the observed continuity.