The causes of the Dakota Conflict are many and complex. The treaties of 1851 and 1858 contributed to tensions by undermining the Dakota culture and the power of chieftains, concentrating malcontents, and leading to a corrupt system of Indian agents and traders. Annuity payments reduced the once proud Dakota to the status of dependents. Annuity payments for the Dakota were late in the summer of 1862. On Sunday, August 17, four Dakota from a breakaway band of young malcontents were on a hunting trip when they came across some eggs in a hen's nest along the fence line of a settler's homestead. When one of the four took the eggs, another of the group warned him that the eggs belonged to a white man. The first young man became angry, dashed the eggs to the ground, and accused the other of being afraid of white men, even though half-starved. Apparently to disprove the accusation of cowardice, the other Dakota said that to show he was not afraid of white men he would go the house and shoot the owner. He challenged the others to join him. Minutes later three white men, a white woman, and a fifteen-year old white girl lay dead. Events moved quickly. Forty-four Americans were killed and another ten captured in the first full day of fighting in and around the Lower Agency at Redwood. Nearly two hundred additional whites died over the next few days as Dakota massacred farm families and attacked Fort Ridgely and the town of New Ulm. By mid-September, the initiative had shifted to the American forces. Penned in to the north and south, facing severe food shortages and declining morale, many Dakota warriors chose to surrender. Together with those taken captive, the ranks of Dakota prisoners soon swelled to 1,250. A decision had to be made soon what to do with them. The trials were quick affairs, getting quicker as they progressed. The commission heard nearly forty cases on November 3, the last day it met. The commission believed that mere participation in a battle justified a death sentence, so in the many cases, perhaps two-thirds of the total, where the prisoner admitted firing shots it proceeded to a guilty verdict in a matter of a few minutes. The final decision on whether to go ahead with the planned mass execution of the 303 Dakota and mixed-bloods rested with President Lincoln. Lincoln asked his clerks to search the records and identify those convicted of participating in the massacres of settlers. The clerks came up with the thirty-nine names included in Lincoln's handwritten order of execution written on December 6, 1862.
Douglas O. Linder,
The Dakota Conflict Trials,
Available at: https://irlaw.umkc.edu/faculty_works/852