How long did the Mongolian empire last?

Who were the Mongolians enemies before Mongolia became an empire?

What was the name of the Mongolian ruler?

1. From 1206 to 1368. That is a total of 162 years.

2. The Tatars where the Mongolians enemies for a while and were wiped out by Mongolians and the only thing that remained was there name.

3. Genghis Khan was the ruler of the mongolia. He turned them from a tribe to a nation.