Fort Snelling, established in 1819, served as a critical military outpost at the confluence of the Minnesota and Mississippi Rivers, marking the western frontier of the United States. Initially, the fort was constructed under Lieutenant Colonel Henry Leavenworth and later named in honor of Colonel Josiah Snelling. It played a significant role during the Civil War and the Sioux outbreak of 1862, functioning as a distribution point while the area around it developed into what is now St. Paul. Its stone structures remain today, reflecting its historical significance.