He was served on the Second Executive Committee of the Provisional Government of Oregon, and his homesite became part of Fort Canby at the mouth of the Columbia River.

[1] During this time Stewart worked as jeweler and watchmaker, and married Rebecca Rawlings Cason on September 1, 1842, in Missouri.

[1] On the journey Stewart is credited with helping fellow immigrant James W. Nesmith with rescuing William Vaughn from drowning while crossing the Kaw River.

[3] Additionally, along the journey the party encountered Lieutenant John C. Frémont of the United States Army, who was on a surveying mission.

[4] After a short time in Oregon, Stewart volunteered to help rescue the Joel Palmer wagon train in 1845.

[1] There he built an "iron house" and saw mill at this site near the entrance of the Columbia River to the Pacific Ocean and Cape Disappointment,[1] near the present-day Ilwaco, Washington.

[1] Lastly, from 1870 to 1879 Stewart served as city recorder for the town of Gervais in the Willamette Valley on French Prairie.

[1] Peter fathered nine children, all by his first wife: Nellie, Margaret, Frederick, James, Katherine, Charles, Catherine, Mary, and George.