Fred MacMurray
Cpt. Meriwether Lewis
Acting
Charlton Heston
Lt. William Clark
Acting
Donna Reed
Sacajawea
Acting
Barbara Hale
Julia Hancock
Acting
William Demarest
Sgt. Gass
Acting
Alan Reed
Charbonneau
Acting
Eduardo Noriega
Chief Cameahwait
Acting
Larry Pennell
Wild Eagle
Acting
Herbert Heyes
President Thomas Jefferson
Acting
Lester Matthews
Mr. Hancock
Acting
Argentina Brunetti
Shoshone Woman (uncredited)
Acting
Julia Montoya
Crow Woman (uncredited)
Acting
Ralph Moody
Chief Le Borgne (uncredited)
Acting
William Phipps
Night Camp Sentry (uncredited)
Acting
Walter Reed
Helmsman Cruzatte (uncredited)
Acting
Bill Walker
Tom (uncredited)
Acting
Helen Wallace
Mrs. Martha Hancock (uncredited)
Acting