Lake County, South Dakota: History
Lake County, South Dakota, was inhabited by the Sisseton Sioux when explorers, including Joseph Nicollet and John C. Fremont, first mapped the region in 1838–39 and noted its numerous lakes. The 1851 Treaty of Mendota with the Santee Sioux and 1858 Yankton Treaty opened the area for American settlement. The 1857 rescue of Mrs. Marble from among the captives of the Spirit Lake Massacre brought early non-Sioux attention to the area.
Permanent settlement began in 1870 when William Lee and Charles Walker established homesteads near Lake Madison, naming the town Madison after Madison, Wisconsin. Lake County was created on January 8, 1873, named for its many lakes, and organized on September 1, 1873, with Old Madison as the county seat. Brisk settlement followed in 1878 amidst the Dakota Boom, and the railroad’s arrival in 1881 spurred growth, with towns like Ramona, Wentworth, and Winfred emerging. By 1880, the county’s population reached 2,657.
Agriculture drove economic progress in the 1870s and 1880s, and Madison became a commercial hub with businesses like the Lake County Flouring Mill (opened 1881), newspapers such as the Madison Sentinel (1879), and the Madison Normal School (1883).