Psychological differences between nations are part of the challenges of globalization. The present study provides benchmarks of personality traits across 12 nations in East Asia and Northern Europe (N = 23,268). Personality was measured with the IPIP-NEO-120, which is a comprehensive, open-source version of the Five Factor Model (FFM). East Asia scored low in Openness and Agreeableness as opposed to high in Europe. Similarly, Neuroticism was higher in East Asia than in Europe. The IPIP-NEO instrument was subjected to measurement equivalence testing, and invariance could not be fully ruled out as part of the explanation. The discussion centers on how to understand the size, the relevance, and the mechanisms of cross-cultural personality differences.