In the 13th and 14 centuries, the Mongols established the largest land empire in human history. At its furthest extent, the Mongolian Empire stretched from the coast of China along the northern border of the Himalayas, encompassing much of today's Middle East from Persia to the Black Sea, much of south-central Russia and Ukraine and Europe to the gates of Vienna. This was done on foot, wagon, and most famously, on horseback. By the time the Mongols reached the eastern borders of Ukraine in the late 1200s, some of their armies numbered 100,000, but it was not their numbers that were the Mongols' primary weapon – terror was. That policy of terror started with their first great leader, the infamous Genghis Khan. He is not infamous everywhere. “The Great Khan”, as he is also known, is still a national hero in Mongolia today.