Kingsbury County, South Dakota: History
John C. Fremont surveyed the area in 1838, naming lakes Preston and Albert. The 1851 Treaty of Mendota with the Santee Sioux and the 1858 Yankton Treaty ceded the region for American settlement. American presence was minimal until the Dakota Boom, with the notable exception of Jacob Hanson's settlement at Lake Albert in 1873.
Settlement surged in 1879 with the Chicago & North Western Railroad’s extension to De Smet. Kingsbury County was created in 1873, named for territorial legislators George W. and T. A. Kingsbury and was organized on December 13, 1879 with De Smet as the county seat. Settlements at Lake Preston, Arlington, and Iroquois grew rapidly, driven by the railroad and fertile prairie lands. By 1880, the county’s population reached 1,234.
Agriculture, particularly corn and wheat, anchored early economic growth, with towns like Lake Preston boasting mills and newspapers by 1881. De Smet gained fame as the setting for Laura Ingalls Wilder’s Little House series, including The Long Winter and Little Town on the Prairie, chronicling her family’s life there from 1879.