Genghis Khan and his heirs converted their leadership of an insignificant, nomadic steppe tribe in northeast Asia into the largest contiguous land empire the world has thus far known, leaving their mark on the statecraft and cultural norms of the world then and now. How was that possible? In recent years, there has been growing debate over how the Mongols accomplished such a feat and what the legacy of that empire has been. Our core book, a readable, revisionist history of Mongol empire-building, argues that a mixture of military and nomadic skills certainly played a role. But more important, Genghis Khan was a visionary. He introduced new concepts of diplomatic immunity, free trade, and a universal rule of law. He promoted religious tolerance, created a meritocratic governance system based on loyalty and achievement, and facilitated unprecedented cultural and commercial exchange across continents. Over time, his empire became a crucible of technological and cultural innovation, bridging diverse civilizations and setting the stage for the modern interconnected world. This SDG will trace the fascinating and layered history of Genghis Khan’s empire building.