The second son of a Cornish landowner, he served as a military officer before emigrating to the Province of Maine in 1630 with his family.
[3] In 1630 or 1631 Bonython emigrated to the fledgling English settlements in the Province of Maine (established under patent by Gorges) in North America.
[3][4] This move may have been triggered by the birth of a son to his elder brother Resymar, who would then inherit the Bonython family estates.
Owing to his previous military service he was held in high regard by the early settlers of Maine and was appointed a magistrate of Saco during the time Richard Vines led the colony.
John had other run-ins with the legal system; in 1645 he threatened to "kill and slay any person that should lay hands on him", and Richard Bonython's court which heard the case afterwards described him as "incapable of any of his Majesty's laws".
[7] Richard Bonython seems to have opposed the Puritan teachings of Saco's Reverend Thomas Jenner, favouring the Church of England.