Fort Laramie. As America expanded westward, Fort Laramie played an important role on the high plains. Founded in 1834 as Fort William, a fur-trading post, it was a center for trade in beaver pelts and buffalo robes, and a place for mountain men, frontier entrepeneurs, and Plains Indians to mingle. Rebuilt in 1841 as Fort John, the new trading post became a welcome stop for emigrants migrating westward along the Oregon Trail and the Mormon Trail.