John Thompson, born in 1841, arrived in America in 1854 as a 13-year-old orphan after his parents and sister died of cholera during the journey from Meraker, Norway, and he was raised by an aunt in Wisconsin. After serving in the Union Army during the Civil War, he moved to Minnesota, married Kirsti Haugen, and in June 1866 the Thompsons and their friends Jonas and Anne Nelson traveled in two oxen-drawn covered wagons to Dakota Territory. Reaching Fort Dakota near the Big Sioux River on June 29, they learned it was unlawful to homestead within the 70-square-mile military reservation around the fort, so they continued north along the river and settled in what is now Sverdrup Township, where by fall they had built a secure 12-foot by 16-foot sod house. John and Kirsti Thompson became the first permanent settlers in Minnehaha County, and their daughter Berthine, born May 26, 1867, was the first white child born in the county. Thompson became prominent in public affairs: the Nidaros Lutheran Congregation was founded in his home on August 12, 1868, and he served as a county commissioner, superintendent of schools, Sverdrup Township board supervisor, assessor, justice of the peace, and for three sessions as a Dakota Territory legislator. In 1892, pioneers organized an Early Settlers' Association, and beginning with its fourth annual picnic in 1895, Thompson's Grove on the west bank of the Big Sioux River became the longtime site of celebrations where pioneers gathered to socialize, hear speeches about the hardships of early Dakota Territory settlement, listen to bands and orchestras, and take part in contests and games. Banks and stores in nearby communities closed so employees could attend, special Milwaukee Railroad trains brought celebrants from Sioux Falls and Dell Rapids, and by 1902 more than 12,000 people were attending. The last picnic was held at Elmwood Park in Sioux Falls in 1939, but Thompson's Grove remained remembered as a gathering place where pioneers shared experiences and celebrated life in early Dakota Territory.