No one knows when the first people came to the land that now comprises Minnehaha County, but native Woodland and Oneota peoples were there over 1000 years ago. The Big Sioux River, which flows south through the county, appeared on maps in Paris in 1702. The Sioux Indians arrived soon thereafter and have lived in the area for over 250 years. Indian country claimed by France was ceded to Spain in 1762 and returned to France in 1800. When Thomas Jefferson bought the Louisiana Territory in 1892, Minnehaha County was part of that purchase. As part of the United States, the area was successively under eight territorial flags: Louisiana, Indiana, Missouri, Wisconsin, Michigan, Iowa, Minnesota, and finally Dakota Territory, organized in 1861. Minnehaha County was created by the Territorial Legislature in 1862. Much of its surface was formed by the Late Wisconsin Glacier about 10,000 years ago, and the falls of the Big Sioux River, formed from Precambrian pink quartzite about 1.7 billion years ago, have been a regional landmark since earliest times. The first European known with certainty to have visited the falls was Philander Prescott in 1832, likely preceded and followed by explorers, trappers, and traders until the first permanent settlers arrived in 1856 by oxcart and covered wagon. The first railroad arrived in 1878 and opened the county to rapid growth. A turbulent era followed, marked by floods, droughts, blizzards, and grasshopper plagues. South Dakota became a state in 1889. By the end of World War I in 1918, sod homes had gradually evolved into prosperous farmsteads. Like the rest of the nation, Minnehaha County was transformed by World War II, with an important Army Air Force Technical School established at Sioux Falls, two interstate highways crossing the county, a large regional airport developing, and new technology transforming agriculture. Sioux Falls is frequently cited as one of the nation’s most attractive places to live, with Minnehaha County sharing the honors.