How did the Aztec civilization maintain control of its vast empire?

Aztecs were able to maintain power in the empire because of Conquering. By conquering, they were able to broaden or widen there territory which made them even more powerful.

The Aztec government was similar to a monarchy where an Emperor or King was the primary ruler. They called their ruler the Huey Tlatoani. The Huey Tlatoani was the ultimate power in the land ... He decided when to go to war and what tribute the lands he ruled would pay the Aztecs