The Mongols were a nomadic people that were lead ultimately by one man to begin to conquer what would quickly be one of the largest empires in history. While war-like and brutal in their conquering, the Mongols were very accepting of other cultures and religions and even let many conquered lands keep their rulers. The entire Mongol empire was made up of Khanates, which were like states each ruled by a secondary ruler to the overall emperor of the Mongols. After Kublai Khan conquered the Song dynasty, he started his own dynasty out of respect for the Chinese, calling it the Yuan dynasty.
This video is an overall description of the Mongol Empire and its culture and famous leaders, as well as its rise and fall of power.
The Mongols as a nomadic people had been led by different khans or chiefs. Genghis Khan (previously Temujin), was one of those khans before he gained ultimate power over the other khans by defeating them. He then preceded to conquer and rule over lands until he had an empire larger than any before him.
The Mongols were incredibly war-like and brutal, but after conquering a people they allowed them to keep nearly all of their customs as well as their rulers and religions. In some cases they even adopted culture traits, such as Islam from Central Asia and Persia.
The first paragraph and the last couple of paragraphs in this link best outline Kublai Khan. He founded the Yuan Dynasty and was the emperor present during its entire height and the beginning of its decline. He had a great respect and fascination for the Chinese, and much of the culture that was picked up by the Mongols from the Chinese was because of him.
The Yuan dynasty was part of Mongol rule, though the Chinese and the Mongols were kept very separate and distinct from one another.
Because the Mongols protected the Silk Road so well, it made it safe for more foreign trade traffic to take place. One of the travelers that traveled from Europe was Marco Polo. After telling his adventures to his cell mate in prison, his cell mate wrote his adventures in a book and published it. As it gained popularity, more people heard of the great wealth of China.