In the first a reasonable time of 13th century, Genghis Khan unified the Mongolian tribes, founding the Mongolian Empire, and led them to overcome many Asia, Central Asia, Russia and center East. Their armies occupied a great element of countries in europe, too, maternity to at least one or higher the largest empires ever. Their cavalry things, especially their horse archers, were Genghis Khan's elite troops and handled, with tough but well coordinated expenses, striking terror for their enemies' hearts.