When the Aztecs decided to conquer a particular city, they would send a leader from Tenochtitlan to offer the city protection and keep them safe. They pointed out the advantages of being able to trade with their Empire.
Archaeologists for a long time believed the ancient Maya to be gentle and peaceful people. Maya warfare was bloody and irresolvable, because limitations of food supply and transportation made it impossible for any Mayan kingdom to unite the whole region with an empire. The archaeological record shows that wars became more intense and frequent toward the time of the collapse.