1. the conquistadors brought small pox with them and that killed MANY people.
2. they had over 20,000 people in their tribe so it was harder for smaller groups to defeat them.
3. they brought secret weapons such as Bulldogs and cannons and the Aztecs didn't know what those even were.
4. when Hernan Cortez wanted to go to battle with the Aztecs, that time of year for the Aztecs was bad because the aztecs were very religious. At that time their god said that this is not a time for battle. so the Aztecs were unprepared
