Colonel Henry Leavenworth established Fort Leavenworth on May 8, 1827. The small cantonment was founded to protect the western frontier, keep peace among Indian tribes resettled to this area, and provide escort on the newly opened Santa Fe Trail. Today the fort is an active military post, home of the U.S. Army Combined Arms Center and the U.S. Army Command and General Staff College. Designated a National Historic Landmark, Fort Leavenworth is the longest continuously active post west of the Appalachians. 8 Wonders of Kansas History