Name Uniqueness and the rise of individualism in the Western hemisphere (1500 - 2000)

• we conducted additional analyses, incorporating Surname Uniqueness, Population, and Year as categorical control variables in our models. 2)We also revisited the Granger causality test, overturning the previous result and have expanded our discussion of these findings. • As for the autocorrelation, we replaced the original analysis with Pearson’s correlation, as our primary objective is to validate the Name Uniqueness Index rather than assess time-series trends. • Additionally, we made minor refinements throughout the manuscript, including correcting citation errors and improving caption clarity. This study investigates the historical evolution of individualism by analysing trends in Name Uniqueness — the distinctiveness of personal names — as a proxy for values emphasising autonomy, independence and self-expression. Using a dataset of 2,313,713 notable individuals from Wikidata (1500–2000), we aimed to capture the historic evolution of Name Uniqueness in the Western hemisphere. Our analysis reveals an increase in individualism in Europe, the Americas, and Australia that predates widespread modernisation, which aligns with the conclusions of historians. In line with modernisation theory, we also observe a strong positive correlation between GDP per capita and Name Uniqueness across five centuries. These results remain robust when controlling for gender, occupation, and time period. Our findings challenge Max Weber’s thesis that the spread of Protestantism is associated with an increase in individualism; in fact, we find that it is associated with a decrease. By combining large-scale historical data with a validated cultural indicator, this study contributes to the growing body of evidence linking economic development to profound shifts in identity and social behaviour. It highlights Name Uniqueness as a powerful tool for tracing the long-term dynamics of individualism in large scale societies.