Comparative studies report the rise of left- and right-wing Eurosceptic parties that have transformed national party competition in Europe toward an inverted U-shaped configuration: peripheral parties at the left and right of the party spec- trum oppose while centrist parties support several features of European integration. To describe the tempo and timing of this transformation and the heterogeneity across countries, we construct a Bayesian finite mixture factor analysis that estimates the election-specific probability of a one-dimensional left/right versus a two-dimensional inverted U-shaped na- tional party configuration. The results show a general trend toward “U” but with significant variation across countries and time, including cases with a reversal of this trend.