The Mongol Empire
The Mongols lived in tribes that were constantly fighting each other. Temuchin changed this though, when he united the tribes and he became known as Genghis Khan. His name means universal ruler. He then decided to focus on military, and built a strong army. The Mongols moved towards China and Korea, defeating them both. Khubilai Khan, who was Genghis' grandson, created a new Chinese dynasty called the Yuan dynasty. They decided to go west, conquering Persia in 1233, Baghdad in 1258, and they had arrived in Europe by the 1230's. They defeated Russia as well as the Teutonic Knights in Silesia. The sole reason that Europe was saved from the Mongols was because the Mongols had a lot of problems with fighting within the ranks, and they had to go back.