Tanya Basu at Science of Us

There’s an assumption about women in power that you may have heard: that women who lead tend to be more diplomatic than their male counterparts, resulting in a more peaceful world. Psychologist Steven Pinker, for instance, wrote in his 2011 book, The Better Angels of Our Nature, “Over the long sweep of history, women have been and will be a pacifying force.” But how much of that is true?

After sifting through historical data on queenly reigns across six centuries, two political scientists have found that it’s more complicated than that. In a recent working paper, New York University scholars Oeindrila Dube and S.P. Harish analyzed 28 European queenly reigns from 1480 to 1913 and found a 27 percent increase in wars when a queen was in power, as compared to the reign of a king. “People have this preconceived idea that states that are led by women engage in less conflict,” Dube told Pacific Standard, but her analysis of the data on European queens suggests another story.

Interestingly, Dube and Harish think the reason why queens were able to take part in more military policy can be explained by the division of labor that tended to happen when a queen — particularly a married queen — ruled. Queens managed foreign policy and war policies, which were often important to bring in cash, while their husbands managed the state (think taxes, crime, judicial issues, etc.). As the authors theorize, “greater division of labor under queenly reigns could have enabled queens to pursue more aggressive war policies.” Kings, on the other hand, didn’t tend to engage in division of labor like ruling queens — or, more specifically, they may have shared military and state duties with some close adviser, but not with the queen. And, Dube and Harish argue, it may be this “asymmetry in how queens relied on male spouses and kings relied on female spouses [that] strengthened the relative capacity of queenly reigns, facilitating their greater participation in warfare.”