Cannon was born in 1755 near Pittsburgh in territory claimed both by Pennsylvania and Virginia.

[3] While a soldier at Michigan's Fort Mackinac in 1810, Cannon was recruited by William Price Hunt to accompany an overland expedition to the Oregon Country.

In his 1836 book, Astoria, Washington Irving related Cannon's unpleasant experience with a grizzly bear during the trip.

Later they traveled to French Prairie, and Etienne Lucier remained with Cannon to help start an American settlement.

[2] In 1843 Cannon was among the immigrants who voted in favor of forming a provisional government in the Oregon Country.