John was the first occupant upon the land of his father in Windham, New Hampshire. Morrison's "History of Windham, N.H." pays the following tribute to the old Stewart homestead in Windham: "The farm is now a pasture, and covered with wood; ministers are entertained there no more; the Stewarts are gone; the buildings disappeared nearly one hundred years ago; the cellar is still there, and from its crumbling and tumble-down walls has grown a birch tree, on which a grapevine has thrown its clinging tendrils. These, with a black currant bush which yearly blossoms and yields its fruit, are all that remains to mark the home of one of the earliest settlers of Windham" (Severance, B. Frank. Genealogy and biography of the descendants of Walter Stewart of Scotland and of John Stewart who came to America in 1718 and settled in Londonderry, N.H. Greenfield, Mass. : T. Morey & Son, 1905, pg. 23-26).

Emigrated to America with his father in 1718. A soldier in the French and Indian War. Among his occupations he was paid to entertain ministers. He entered service March 26, 1760 under Col. John Goffe, Alexander Todd, Captain, for the invasion of Canada. The regiment went to Crown Point. They were forty-four days in cutting their way to the foot of the Green Mountains which they crossed by packing and hauling their stores over mountains on horse harrows. He died from the effects of hard service in this expedition.