Genghis Khan worshipped a god called Tengri, and he believed that he had the god-given duty to conquer. However, Genghis Khan was tolerant of other religions and even admired the wise men other faiths had to offer. The lands conquered by Genghis Khan were managed through a pretty elaborate bureaucracy, and post houses were established along trade routes. Trading actually became much safer in the areas conquered by Genghis, because the other nomads living in these areas were recruited as gamekeepers and guards and were able to keep out unwanted intruders.

By today's standards he would be a con.

In today's time he would be considered a dictator. Depending on how much oil his country has he might be an ally of the U.S.