Zenas Leonard was a mountaineer, fur trader and trapper. From the book, it is established that Zenas' parents lived in Clearfield, Pennsylvania in the 1830s. He left his home, in 1830, going first to Pittsburgh, before embarking on en expeidition to the Rocky Mountains.
Zenas married Isabel Harrelson, and they had a son, Zenas Leonard, Jr., born 1846, of Missouri, who was the father of William D. Leonard of Kansas City c. 1934. Zenas and Isabel had two other children, as well.
Read about the life of a trapper in Leonard's Narrative, Adventures of Zenas Leonard, fur trader and trapper, 1831-1836, by Zenas Leonard, 1809-1858, William F. Wagner, 1865- , published 1904, free here:
For more Leonard history, see the Leonard page.