Miles Goodyear was a mountain man during the last years of the fur trade who built and occupied Fort Buenaventura in what is now Ogden, Utah. Goodyear was born in Hamden, Connecticut, on 24 February 1817 and was orphaned at the age of four. After serving much of his youth as a "bound Boy," or indentured servant, he determined to travel west to seek his fortune. In 1836, when he was nineteen, he joined the Whitman-Spaulding missionary party traveling west on the Oregon Trail from Independence, Missouri. Goodyear was described by his fellow travelers as "thin and spare," with "light flaxen hair, light blue eyes." As time passed, Goodyear's hair turned red. At Fort Hall, Goodyear decided to leave the party (which had brought the first white women west on the Oregon Trail). William H. Gray described Goodyear as he left them: "His idea of liberty was unlimited. Restraint and obedience to others was what he did not like at home; he would try his fortune in the mountains; he did not care for missionaries, Hudson's Bay men, nor Indians; he was determined to be his own man . . . ."

For the next decade, Miles Goodyear trapped, traded, and was by all accounts a successful mountain man. By 1839 he had married Pomona, daughter of the Ute Chief Pe-teet-neet, and by 1842 they had two children, William Miles and Mary Eliza. Goodyear ranged widely across the Rocky Mountains, trapping, trading, and visiting various gatherings of mountain men and Indians, including the rendezvous of 1843. In a letter sent to his brother in 1842 Goodyear wrote that he had not yet made his fortune but did have "property, horses, beaver, and $2,500."