The United States gained ownership of Minnesota through the Louisiana Purchase of 1803. However, this wild land did not come under the control of the U.S. government for several more years. Fort Snelling was completed at the confluence of the Mississippi and Minnesota rivers in 1825. This fort, named after Colonel Josiah Snelling, who was charged with its construction, was key to controlling the fur trade, as well as settlement of the Northwest. The activities and protection of the fort directly contributed to the founding of the settlements of St. Anthony and Pig’s Eye. Later, these settlements were renamed Minneapolis and St.Paul, respectively – Minnesota’s Twin Cities. By 1851, Fort Snelling’s military importance had diminished and it became a supply depot. During the Civil War, it became a training center for volunteers. It was again used for training soldiers during World War II. In 1960, the fort became Minnesota’s first historic landmark. In 1960, it was designated a National Historic Landmark and restored to its original condition.