This paper develops an empirical measure of growth poles and uses it to examine the phenomenon of multipolarity. The authors formally define several alternative measures, provide theoretical justifications for these measures, and compute polarity values for nation states in the global economy. The calculations suggest that China, Western Europe, and the United States have been important growth poles over the broad course of world history, and in modern economic history the United States, Japan, Germany, and China have had prominent periods of growth polarity. The paper goes on to analyze the economic and institutional determinants, both at the proximate and fundamental level, that underlie this measure of polarity, as well as compute measures of dispersion in growth polarity shares for the major growth poles.