The Mongolian Dynasty
The Mongolian Empire was originally divided up and they just invaded others. But after awhile one main person by the name of Genghis Khan stepped up to lead them. With his followers, he built the largest land empire modern history.
Also the Yuan Dynasty, who was led by Kublai Khan, is considered to also be apart of the Mongol Dynasty, discovered most of China's geographical features by using Marco Polo to go around China and find different land marks.