Next to China is the Gobi Desert, and it was inhabited by nomadic people known as the Mongols.
Genghis Khan was born in 1162, and was part of the Borjigin tribe. His birth name was actually Temujin. When he was a boy he was always headstrong and never needed advice.
At age 16, he married a girl named Borte, making an alliance with her tribe and his. They had four children together, and Temujin also had many other children through his other wives, which was a common Mongol custom.
Temujin was captured during one of his early raid he made, he was enslaved, but escaped with help of some friends of his. After this, he assembled his own arm and began to form the Mongolian Empire.
Temujin was a very good military strategist and he led a very skilled group of soldiers.
He had mastered unique communication tactics, and also how to ride a horse without using hands, which allowed them to use their weapons in battle, Temujin also instituted a spy network to identify enemies.
Temujin invaded the lands of the Muslims and destroying everything in his way, this invasion, in 1219, gave Temujin control of much of Central Asia and Eastern Europe, and ended the Khawarizm dynasty.
Genghis did instituted a law called the Yassa.
We still are not really sure of how Genghis Khan died.