Me and Pip

Two adventuresome young boys, one white, one black, leave the Great Dismal Swamp in Virginia and head west in 1830 to see the Rocky Mountains that they've heard about.
They drive freight wagons down the Santa Fe Trail, learn the beaver trade, and attend the Great Rendezvous of 1833. It's the first book in a series, as only R. O. Lane can tell it.