In one of those "blow your mind" discoveries of unsung women in history comes the story of the daughters of Genghis Khan. I've never heard that he had daughters, let alone daughters who "ruled the largest empire the world has ever known."
Jack Weatherford, the former DeWitt Wallace Professor of anthropology at Macalester College in Minnesota, is best known for his 2004 book, Genghis Khan and the Making of the Modern World. After its publication, he researched and wrote The Secret History of the Mongol Queens: How the Daughters of Genghis Khan Rescued His Empire.
He says "Genghis Khan sired four self-indulgent sons who proved good at drinking, mediocre at fighting, and poor at everything else; yet their names live on despite the damage they did to their father's empire. Although Genghis Khan recognized the superior leadership abilities of his daughters and left them strategically important parts of his empire, today we cannot even be certain how many daughters he had…[but] without Genghis Khan's daughters, there would have been no Mongol empire."