What are the reasons the Aztec and Incas were declined?

Are the Olympians real? Why is Eris important to the Trojan War? What is the greet origin of the word furious? What does the layout of catal huyuk reveal about early life there? What is the myth behind Anastasia Romanov? Why did Spain want the Amistad africans returned? What are the cause and effects of greek mythology? A traveling poet-musician? When telemecus comes home who was the first person to recognize him? Did Pachacuti get married? Where did Cleopatra come from? Did Sir John Harington invent the toilet? When was Cupid's Rival created? How long did it take it build the mall of America? What did Cronus do to his first four children? What feature of the polis made it a safe protected place to live and conduct business? What was a portable funeral bed in ancient rome? How many mummies are there in the world? When did the second century begin? Where did the lotus eaters come from in The Odyssey?