Cotton Mather, writing homework help

Please describe for me what Cotton Mather means in the following passage from The Wonders of the Invisible World. In your response, please think about how this passage fits into the American context of what Puritans believed and why they were so intent on settling and subduing this “new” land. Be as textual and specific as you can be.

“The New Englanders are a people of God settled in those, which were once the devil’s territories; and it may easily be supposed that the devil was exceedingly disturbed, when he perceived such a people accomplishing the promise of old made unto our blessed Jesus, that He should have the utmost parts of the earth for His possession.”

Thanks for help!