Brookings County, SD

1851: Traverse de Sioux – All land east of the Big Sioux, which included the areas of Brookings County, much of western Minnesota and eastern Iowa, was signed over to the United States government by the upper bands of the Dakota nation.

1856: Sioux Falls is established. 

May 1857: The first two settlements in Brookings County, Flandreau (named for Judge Charles E. Flandreau) and Medary (named for Governor Samuel Medary of the Minnesota Territory) were established. 

April 1858: A new treaty was signed after Traverse de Sioux proved ineffective. 

June 1858: The first Medary settlement was abandoned after Native American attack. 

1861: Civil War began in the United States of America. 

1862: The Dakota War started in Minnesota. Here is some information from History.com: 

“Dakota Indians attacked white settlements along the Minnesota River. The Dakota were eventually overwhelmed by the U.S. military six weeks later. 

The Dakota Indians were more commonly referred to as the Sioux, a derogatory name derived from part of a French word meaning "little snake." They were composed of four bands, and lived on temporary reservations in southwestern Minnesota. For two decades, the Dakota were poorly treated by the Federal government, local traders, and settlers. They saw their hunting lands whittled down, and provisions promised by the government rarely arrived. Worse yet, a wave of white settlers surrounded them. 

The summer of 1862 was particularly hard on the Dakota. Cutworms destroyed much of their corn crops, and many families faced starvation. Dakota leaders were frustrated by attempts to convince traders to extend credit to tribal members and alleviate the suffering. On August 17, four young Dakota warriors were returning from an unsuccessful hunt when they stopped to steal some eggs from a white settlement. The youths soon picked a quarrel with the hen's owner, and the encounter turned tragic when the Dakotas killed five members of the family. Sensing that they would be attacked, Dakota leaders determined that war was at hand and seized the initiative. Led by Taoyateduta (also known as Little Crow), the Dakota attacked local agencies and the settlement of New Ulm. Over 500 white settlers lost their lives along with about 150 Dakota warriors. 

President Abraham Lincoln dispatched General John Pope, fresh from his defeat at the Second Battle of Bull Run, Virginia, to organize the Military Department of the Northwest. Some Dakota fled to North Dakota, but more than 2,000 were rounded up and over 300 warriors were sentenced to death. President Lincoln commuted most of their sentences, but on December 26, 1862, 38 Dakota men were executed at Mankato, Minnesota. It was the largest mass execution in American history.” 

Due to fear of attack, Sioux Falls and Flandreau were abandoned until 1865.