Found this on the internet -- a good launch point.

My 7th great-grandfather bought 550-acres abutting the entire south half of what is now Casco Bay (Portland, ME) from Anthony Brackett in the early 18th Century. Historical accounts reference Brackett acquiring the land once owned by Sir Ferdinando Gorges. ...but fail to explain HOW this land was granted. Was there a transaction and/or governing body?

Ferdinando never set foot in the New World, but what really intrigues me is how many settlers migrated north into what is now Maine in the late 1600s. What was the incentive? It was a very well known "hazard region" involving hostile interactions with natives. Said Brackett was captured multiple times, family murdered or captured, etc. His wife devised their first escape. source2 source3 source4 -- this one's a good yarn.

God only knows how/why my 7th great-grandfather was inspired to migrate to this region. Seems there had to be an incentive. His father and grandfather were men of "prominence" in Newburyport; held public office etc. Thoughts? My ancestor in question DID go on to become instrumental in the formation of what is now Portland, ME ...but his incentive in migrating north amidst frequent conflict with natives is very intriguing.