The empire led by Genghis Khan during the 13th century was the Mongol Empire. It expanded rapidly, becoming the largest contiguous empire in history. Genghis Khan united various Mongol tribes and initiated a series of military campaigns that conquered vast territories across Asia and into Europe. His organizational and military strategies allowed for unprecedented mobility and coordination, leading to the establishment of trade routes that facilitated cultural exchange, known later as the Pax Mongolica. The empire's influence is evident in the impacts it had on trade, culture, and political structures in the regions it conquered, leaving a lasting legacy.