In 1851, the eastern Dakota (Sioux) tribes, gave into pressure from the US Government and sold 35 million acres across western and southern Minnesota. The Dakota moved onto a small reservation along the Minnesota River just north of New Ulm that extended to present day South Dakota border.

After several years of late payments by the US Government for the land coupled with corrupt Indian Agents and unfair trading practices by the fur traders, on top of crop failures and drought was enough to increase tensions. Payments for the land, if they arrived at all, were late. The Indian Agents were paying the fur traders whatever they asked for supposedly paying the Dakota's debts rather than giving the tribes the monies so they could purchase needed food. They tribal hunting grounds were disappearing and game became scarce. Many were starving.

When Minnesota became a state in May 1858, Chief Little Crow led a band to Washington DC to negotiate for enforcing the treaties. However, as part of the negotiations, the northern part of the reservation along the Minnesota River was lost as were rights to the quarry at Pipestone. Little Crow lost standing in the tribal community with these losses.

The lands ceded were marked for township and opened for settlements. Timber was logged and agriculture started. This further disrupted the available hunting and the remaining land on the reservation wasn't arable. This also diminished the tribes ability to sell furs to traders in exchange for badly needed supplies.

On 4 Aug 1862, northern Sissetowan and Wahpeton Dakota tribal representatives went to the Upper Sioux Indian Agency and received food. When the southern Mdewakanton and the Wahpekute tribal representatives went to the Lower Sioux Indian Agency 15 Aug 1862, the Indian Agent (and senator) Thomas Galbraith refuses to give out food without payment. In a meeting with local government leaders, Dakota representatives and the representative of the government traders, Andrew Jackson Myrick, in order to obtain food on credit. Myrick is reported to have said, "So far as I am concerned, let them eat grass." Myrick would apparently not live long enough to regret his words.

On 16 Aug, the payments arrived at St Paul and were sent to Fort Ridgely the next day. However, the payments were too late to prevent violence.

On 17 Aug, four young Dakota warriors on a hunting trip in Acton Township, killed five whites and stole food. The next day, a tribal council met and, with Little Crow's leadership, agreed to continue attacks on European-American settlements to hopefully drive the whites out. On 18 Aug, Little Crow led a group that attacked the Lower Sioux (aka Redwood Agency) Agency. Andrew Myrick was among the first killed. He was found with grass stuffed in his mouth. The warriors burned the buildings at the agency, accidentally giving the settlers time to escape across the ferry. Minnesota militia and Company B of the 5th Minnesota Volunteer Infantry were sent to stop the warriers, but were defeated at the battle of Redwood Ferry. Warriors killed 24 soldiers including Capt John Marsh the commander. Throughout the day, settlements were attacked and burned, including townships of Milford, Leavenworth and Sacred Heart. The populations of these settlements were almost extinguished.

Filled with confidence, the Dakota attacked the New Ulm Settlement on 19 Aug and 23 Aug. Although the town's defenses held against the attack, the Dakota were able to burn much of the town. A thunderstorm dampened the rampage. Regular soldiers and militia, including two companies of the 5th Minnesota Volunteer Regiment from Fort Ridgely, helped reinforce the town.

Initial plans by the Dakota were to avoid Fort Ridgely, however, plans changed and they attacked the fort 20 and 22 Aug. The Dakota were not able to take the fort, but they did ambush a relief party on it's way to New Ulm on 21 Aug. These attacks limited the fort's effectiveness to aid outlying settlements. The Dakota continued to raid farms and settlements throughout south central Minnesota and what was then eastern Dakota Territory.

On 2 Sep, a detachment of 150 soldiers were sent out to look for survivors and bury the dead. At Birch Coulee, 16 miles from Fort Ridgely, they met with the Dakota warriors. An early morning assault started the three-hour battle. Thirteen soldiers were killed and 47 wounded. Only 2 Dakota lost their lives. That afternoon, a column of 240 soldiers from Fort Ridgely relieved the detachment.

Further north, Dakota warriors attacked unfortified stagecoach stops on the Red River Trails, which ran from Fort Garry (now Winnipeg, Manitoba) to St Paul through the Red River Valley in northwestern Minnesota and eastern Dakota Territory. Settlers and employees of various businesses to refuge at Fort Abercrombie (near present day Fargo, North Dakota). The Dakota attacked the fort several times unsuccessfully. However, trade along the Red River was halted, as mail carriers, stagecoach drivers and military couriers were all killed along the route. Eventually, the garrison at Fort Abercrombie was relieved by a US Army company from Fort Snelling and the civilians were returned to St Cloud.

Although the US forces continually requested aid, it was largely ignored because of the requirements of the Civil War. Finally, President Abraham Lincoln sent Gen John Pope to stop the violence and return some normalcy to the area. Pope led the 3rd and 4th Minnesota Volunteer Infantry Regiments. Former Governor Henry Hastings Sibley also responded to with some forces.

With the larger force, the final large-scale battle took place 23 Sep 1862 at Wood Lake. The Dakota forces were defeated overwelmingly. Most of the Dakota surrender at Camp Release 26 Sep 1862. Camp Release is where the Dakota released 269 captives to Sibley's troops. Most of the warriors were imprisoned before Sibley arrived. They were held until military trials took place in November.

Little Crow, forced to retreat, went to Canada, but returned later to Minnesota. He was shot and killed while picking raspberries with his teenage son near Hutchinson, Minnesota 3 Jul 1863 by Nathan Lamson. When the body was identified as Little Crow, Lamson received the usual bounty plus and additional $500. For his part in the war, Little Crow's son was sentenced to death, but his sentence was reduced to life in prison.

In Dec 303 Dakota prisoners were sentenced to death. The Dakota were not represented, nor were they apprised of the proceedings. Many trials lasted less than five minutes. Pres Lincoln reviewed each and every trial to determine who had participated in war versus those who attacked and committed attrocities against the civilians. Lincoln ultimately reduced the sentence of 264 to life in prison and only 39 were sentenced to die.

The clemency granted to the Dakota caused such an uproar that civilians who had suffered at the hand of the Dakota were offered reasonable compensation. Lincoln was reportedly told that he would have fared better at election time had he not granted clemency.

One of the 39 was also granted clemency later, as only 38 were hung 26 Dec 1862 in Mankato, Minnesota. This was the largest mass execution in American history. The bodies were buried in a mass grave. Because of the high demand for cadavers, the grave was reopened and the bodies were distributed among local doctors. William Worrall Mayo received the body of He Who Stands in the Clouds. In the late 20th century, the Native American bodies were returned to the tribe by the Mayo Clinic for reburial.

At least two Dakota leaders, Little Six and Medicine bottle escaped to Canada. They were found, drugged and returned to the US where they were hanged at Fort Snelling in 1865.

The remaining convicted Dakota were held in prison over the winter. In the spring, they were transferred to Rock Island, Illinois where they were held for four years. A third died from disease. The survivors were released with their families to Nebraska.

During this time, 1600 Dakota women, children and old men were kept imprisoned at Pike Island near Fort Snelling. Living conditions and sanitation were poor and when an infectious disease struck, it killed more than 300. In April 1863, the island reservation was abolished, all previous treaties declared null and void, and the Dakota were expelled from Minnesota. A bounty of $25 was placed on the head of any free Dakota within the boundaries of Minnesota. The only exception was the 208 Mdewakanton who assisted the white settlers or remained neutral during the violence.

The Dakota survivors in May 1863 were sent by steamer to Crow Creek Reservation in southeastern Dakota Territory. This area had been stricken by a drought during this time. Many of the survivors of Crow Creek several years later moved to the Niobrara Reservation in Nebraska.

Many of the settlers that had fled during the violence did not return. In the aftermath of the Civil War, however, settlers resettled the area once wracked by violence.

Many years later, The Lower Sioux Indian Reservation was established near Morton. Several years later, the Upper Sioux Indian Reservation was established near Granite Falls.