McCann (2015) showed that American states with lower mean levels of resident neuroticism have higher rates of residential mobility. The present research tested the hypothesis that state resident neuroticism correlates negatively with state entry order. The hypothesis was derived from McCann’s residential mobility theory and based on restricted gene pools producing lower resident neuroticism as successive areas gained statehood. Spearman correlation confirmed that state resident neuroticism levels correlated highly (−.72) with state entry order. With state entry order transformed to a standard normal distribution, sequential multiple regression showed that the relation could not be accounted for by recent state differences in socioeconomic status, urban population percent, White population percent, Black population percent, Hispanic population percent, sex ratio, median age, or pathogen prevalence level. Supplementary analyses replicated the results with an alternate neuroticism measure and found that the other Big Five personality variables did not play a part in this context. The results are consistent with an evolutionary perspective. One common adaptive problem humans have faced repeatedly is residential relocation and migration. As with other adaptive problems central to important recurring situations, psychological mechanisms referred to as adaptations have evolved. From this perspective, personality differences are adaptations that reflect ways in which individuals characteristically deal with adaptive problems. They also determine which adaptive problems to confront or avoid. Therefore, in different environmental contexts, personality traits have different fitness consequences. Higher and lower neuroticism indeed appear to function as alternative strategies for solving the recurrent adaptive problem of residential relocation or migration. (PsycINFO Database Record (c) 2018 APA, all rights reserved)