Why did the hittites and others migrate from central asia to mesopotamia?

Because of the Fertile Cresent which is a fertile strip of farmland. It is near Asia Minor, Egypt, and Mesopotamia. But each group didn't stay long because there were no natural barriers and invaders came in. The first settlers in the Fertile Cresent were the Sumerians. Hope this helped!

The second , larger puritan colony of massachusetts bay was conceived as a "city upon a hill". but it also struggled with internal turmoil like the salem witch trials and external conflicts like king philip's (metacom's) war.